Unit 2 Summary. Goal Use this page to review the concepts in Unit 2, Chemical Reactions and Radioactivity.

Transcription

1 UNIT 2 BLM 2-1 Unit 2 Summary Goal Use this page to review the concepts in Unit 2, Chemical Reactions and Radioactivity. Chapter 4 Atomic theory explains the formation of compounds. Atoms are neutral. In ions, the number of electrons and protons differ, giving the ion an electrical charge. (4.1) Compounds containing a metal and a non-metal usually form ionic compounds in which positive and negative ions are connected by ionic bonds. Compounds containing only nonmetals form molecules in which the atoms are connected by covalent bonds. (4.2) Chemical equations are words or symbols that identify the reactants and products in a chemical reaction. (4.3) The law of conservation of mass states that the total mass of all the reactants in a chemical reaction is equal to the total mass of all the products. (4.3) Chapter 5 Compounds are classified in different ways. The formula of an acid has an H on the left side. The formula of a base has an H on the right of a metal. A salt is an ionic compound formed from an acid-base neutralization. (5.1) The ph scale is a way of measuring the concentration of the H+ ion. A neutral solution has a ph = 7, an acidic solution has a ph < 7, and a basic solution has a ph > 7. (5.2) xides that contain a metal react with water to form basic solutions. xides that contain only non-metals react with water to form acidic solutions. (5.2) rganic compounds are compounds that contain carbon and usually contain hydrogen. (5.3) Chapter 6 Chemical reactions occur in predictable ways. Chemical reactions can be classified as synthesis, decomposition, single replacement, double replacement, neutralization (acid-base), or combustion. (6.1) It is possible to predict the identity of the products of a reaction based on its classification and knowledge of the reactants. (6.1) Factors that affect the rate of a reaction include temperature, concentration, surface area, and the presence of a catalyst. (6.2) A catalyst is a substance that speeds up the rate of a chemical reaction but is still present in its original amounts at the end of the reaction. (6.2) Chapter 7 The atomic theory explains radioactivity. Isotopes are atoms of the same element that differ in the number of neutrons that they possess. (7.1) Radioactive decay results from changes in the nucleus of an atom and can produce alpha, beta, and gamma radiation. (7.1) A half-life is the length of time required for half the nuclei in a sample of a radioactive isotope to decay into its products. (7.2) Nuclear reactions involve the splitting of heavy nuclei (fission) or the joining together of lightweight nuclei (fusion), both of which can release large amounts of energy. (7.3) Radioactive decay, fission, and fusion reactions are symbolized using nuclear equations. (7.3)

2 UNIT 2 BLM 2-2 Unit 2 Words to Know Goal Use this page to review the Unit 2 Words to Know. Chapter 4 atomic number atoms balanced chemical equation binary covalent compound Bohr diagram chemical equation chemical reaction compound conservation of mass covalent bonding electrons ionic bonding ionic compounds ions Lewis diagram molecule neutron polyatomic products proton reactants skeleton equation subscript symbolic equation valence electrons Chapter 5 acids alcohol bases bromothymol blue concentration hydrocarbon indigo carmine inorganic litmus paper metal oxide methyl orange non-metal oxide organic organic chemistry oxide ph indicators phenolphthalein salts solvent Chapter 6 catalyst catalytic converter combustion decomposition double replacement neutralization (acid-base) precipitate rate of reaction single replacement surface area synthesis Chapter 7 alpha particle beta particle chain reaction daughter isotope decay curve fission fusion gamma radiation half-life isotopes light mass number nuclear equation nuclear reaction parent isotope radiation radioactive decay radiocarbon dating

3 CHAPTER 4 BLM 2-3 Interpreting an MSDS Goal Demonstrate your understanding of the information on a chemical label and on a Material Safety Data Sheet (MSDS). What to Do Answer each question in the space provided. 1. The label from a container of a chemical that is commonly used in high-school laboratories is shown below. Refer to this label to answer the questions that follow. (a) According to the chemical label, what is the name and chemical formula of the substance? (b) Is the substance dangerous to your health? If so, in what way is it dangerous? (c) What safety precautions should you take when handling the substance during an investigation?

4 BLM 2-3 continued (d) How should you dispose of excess amounts of the chemical? (e) A fellow student has accidentally swallowed some of the chemical. What should you do? 2. Your teacher has given you an MSDS for another chemical that is commonly used in high school laboratories. Refer to this MSDS to answer the following questions. (a) According to the MSDS, what is the name and chemical formula of the substance? (b) Is this substance dangerous to your health? If so, in what way is it dangerous? (c) What safety precautions should you take when handling the substance during an investigation? (d) In the event of a fire, what safety precautions should firefighters take? (e) A large quantity of the substance has been spilled on the floor of the laboratory. What steps should be taken to clean up the spill? (f) Where should you store the substance when you are not using it?

5 CHAPTER 4 BLM 2-4 Anatomy of an Atom Goal Review features of a simplified modern model of the atom. Electrons A fuzzy, cloudlike region surrounds the nucleus. exist in this region at certain allowed energy levels. An atom consists of a tiny, dense nucleus that is surrounded by electrons. The nucleus contains protons and neutrons. (An exception is the hydrogen-1 nucleus, which contains one proton only.) Protons and neutrons are also called nucleons. The nucleus accounts for most of the mass of the atom. Electrons exist at certain allowed energy levels. Electrons occupy the volume that accounts for most of the volume of the atom. Protons carry a positive charge. Electrons carry a negative charge. Neutrons carry no charge. A neutral atom always has equal numbers of electrons and protons. Properties of Protons, Neutrons, and Electrons Subatomic Particle Relative Charge Symbol Mass (g) Relative Mass Radius (in m) Proton 1+ p Neutron 0 n Electron 1 e /1850 Smaller than 10 18

6 CHAPTER 4 BLM 2-5 The Periodic Table Goal Use the periodic table to learn more about elements.

7 CHAPTER 4 BLM 2-6 Bohr Diagrams Goal Use this page to review Bohr diagrams for the first 20 elements.

8 CHAPTER 4 BLM 2-7 Lewis Diagrams Goal Use this page to review Lewis diagrams for the first 18 elements.

9 CHAPTER 4 BLM 2-8 Periodic Table Scavenger Hunt Goal Demonstrate your understanding of the periodic table. What to Do Use your periodic table to answer the following questions. 1. Identify each element. (a) The element in group 5 and period 5 (b) nly halogen that is a liquid at room temperature and pressure (c) Alkali metal with the most massive atoms (d) Synthetic element in period 5 (e) Metal in group 16 and period 4 (f) Alkaline earth element with the least massive atoms (g) Noble gas that has atoms with 54 protons 2. Complete the following table. The first row is completed as an example. Name of Element Atomic Number Number of Protons Number of Electrons silicon chromium sodium Shade in the following chemical families, as indicated, on the outline of the periodic table.

10 CHAPTER 4 BLM 2-9 Understanding Lewis Diagrams Goal Demonstrate your understanding of Lewis diagrams. What to Do 1. Complete the following table. Name of Element Period Number Group Number helium 18 Number of Energy Levels Number of Valence Electrons strontium Draw the missing Lewis diagrams in the following table. Refer to a periodic table as necessary.

11 CHAPTER 4 Bohr Diagrams and Lewis BLM 2-10 Diagrams Goal Practise drawing Bohr diagrams and Lewis diagrams. What to Do Complete the following table by drawing both the Bohr diagram and Lewis diagram for each element. The first row is completed as an example. Name of Element Bohr Diagram Lewis Diagram carbon oxygen lithium chlorine magnesium phosphorus

12 CHAPTER 4 BLM 2-11 Modelling Compounds Goal Record your drawings for Think About It 4-1B, Modelling Compounds. What to Do Use these charts to draw Bohr diagrams and Lewis diagrams for Think About It 4-1B, Modelling Compounds, on page 181 of your student book.

13 CHAPTER 4 BLM 2-12 Binary Ionic Compounds Goal Demonstrate your ability to write the names and formulas of binary ionic compounds. What to Do 1. Complete the following table. Name of Compound Formula (a) beryllium fluoride (b) sodium nitride (c) calcium sulphide (d) aluminum chloride (e) lithium oxide (f) magnesium nitride (g) gallium sulphide (h) barium bromide

14 CHAPTER 4 Names and Formulas of Binary BLM 2-13 Ionic Compounds Goal Use this page to review the names and formulas of binary ionic compounds. What to Do 1. Fill in the missing names of these ionic compounds. Formula Metal Ion Name of Compound (a) FeCl 3 Fe 3+ (b) Fe Fe 2+ (c) Cu 2 S Cu + (d) Pb 2 Pb Fill in the missing formulas for these ionic compounds. Name of Compound (a) copper(i) oxide Chemical Formula (b) lead(iv) bromide (c) iron(iii) sulphide (d) nickel(iii) fluoride (e) manganese(iv) sulphide 3. Fill in the missing names for these ionic compounds. Formula Name of Compound (a) Ti 2 3 (b) NaCl (c) CuCl 2 (d) N 2

15 CHAPTER 4 BLM 2-14 Chemical Names and Formulas Goal Review your understanding of chemical names and formulas. What to Do Complete the following table. Chemical Formula Ionic or Covalent? Name of Compound 1. NH 4 Cl 2. potassium sulphide 3. CI 4 4. calcium oxide 5. ammonium chloride 6. Li 3 N 7. Mg(H) 2 8. zinc oxide 9. CuN oxygen dichloride 11. CuCl 12. FeCl carbon tetrabromide 14. aluminum chromate

16 CHAPTER 4 BLM 2-15 Chemical Compounds Goal Use this page to identify chemical compounds. 1. Complete the following table. Name Formula Ionic or Covalent? (a) (b) NaCl Mg (c) lithium iodide (d) carbon dioxide (e) strontium hydroxide (f) K 2 S (g) CuBr 2 (h) sulphur trioxide (i) Ba 3 (P 4 ) 2 (j) aluminum hydroxide (k) oxygen difluoride (l) NH 4 CN (m) Fe(N 3 ) 3 (n) gold(iii) sulphate (o) iron(ii) carbonate (p) carbon tetraiodide (q) FeI 3 (r) dinitrogen trioxide

17 CHAPTER 4 BLM 2-16 The Crossover Method Goal Learn an alternative method for writing formulas. What to Do The crossover method is a shortcut that can help you determine the formula of an ionic compound. To use the crossover method, follow the steps below. 1. Write the formulas of the ions beside each other. 2. Cross over the magnitude (amount or size) of the charge on the cation (positive ion) so that it is the subscript for the anion (negative ion). 3. Cross over the magnitude of the charge on the anion so that it is the subscript for the cation. 4. Reduce to lowest terms if necessary. 5. Check your formula. Model Problem 1 Determine the formula of each compound. (a) magnesium chloride (b) calcium oxide Solution (a) Determine the subscripts by crossing over the magnitudes of the charges. Remember that you do not write the number 1. magnesium chloride Check the formula by adding the charges on the ions: +2 + [2 ( 1)] = 0 The total charge is zero. The formula is correct. (b) Because a formula shows the ratio of ions, you must write the simplest ratio. For calcium oxide, the simplest ratio of ions is 1:1. Ca calcium oxide Check the formula by adding the charges on the ions: +2 + ( 2) = 0 The total charge is zero. The formula is correct.

18 BLM 2-16 continued The Reverse Method You can use the reverse of the crossover method to determine the charge of a polyatomic metal ion in an ionic compound. Model Problem 2 Determine the charge on Fe in each compound. (a) FeCl 3 (b) Fe Solution (a) Use the reverse of the crossover method. Add the charge signs to each ion. Remember that you do not write the number 1. Check your answer. The charge on Cl is correct (1 ), therefore the cation charge must be correct. In FeCl 3, the iron cation is Fe 3+. (b) Use the reverse of the crossover method. Add the charge signs to each ion. Check your answer. The charge on is incorrect. The oxygen anion should be 2, not 1. You need to double the charge on each ion. Therefore, the iron cation in Fe is Fe 2+. Practice Problem 2. Use the reverse crossover method to determine the charge on the positive ion in each compound. Show your work. (a) Cu 2 (b) NiBr 2 (c) Pd (d) Ti 2

19 CHAPTER 4 Check Your Understanding BLM 2-17 Charts Goal Use these charts to complete your answers to questions 6 and 11 on page 201. What to Do Record your answers below for questions 6 and 11 on page 201 of your student book

20 CHAPTER 4 BLM 2-18 Balancing Chemical Equations Goal Practise writing skeleton equations and balanced equations. 1. Word equation iron + sulphur iron(ii) sulphide Skeleton equation Balanced equation 2. Word equation Skeleton equation Balanced equation calcium + oxygen calcium oxide 3. Word equation Skeleton equation Balanced equation calcium oxide + carbon dioxide calcium carbonate 4. Word equation Skeleton equation Balanced equation copper(ii) oxide copper + oxygen 5. Word equation Skeleton equation barium chloride + potassium sulphate barium sulphate + potassium chloride Balanced equation 6. Word equation Skeleton equation Balanced equation potassium + water potassium hydroxide + hydrogen

21 CHAPTER 4 BLM 2-19 Atomic Theory and Bonding Goal Use this page to review the concepts of the atomic theory and bonding. What to Do Circle the letter of the best answer. 1. Which statement is true of elements in the same period in the periodic table? A. They share similar properties. B. They have the same atomic mass. C. They cannot react with each other. D. They have the same number of energy levels. 2. Which Lewis diagram correctly represents a nitrogen atom? A. B. C. D. 3. How many protons does an atom of silver contain? A. 47 B. 108 C. 61 D What does a Lewis diagram show? A. unpaired electrons only B. valence electrons only C. electrons from the innermost energy level only D. all the electrons in an atom 5. An atom is found to have seven valence electrons. To which family of elements in the periodic table does this atom belong? A. noble gases B. halogens C. alkaline earth metals D. alkali metals 6. What is the nucleus of any atom, except hydrogen, made up of? A. only neutrons B. only protons C. equal numbers of electrons and protons D. neutrons and protons

22 BLM 2-19 continued 7. What is the name of the compound Fe 2 3? A. iron(iii) oxide B. iron oxide C. iron(ii) oxide D. iron(ii) trioxide 8. What is the name of the compound S 2 3? A. sulphur oxide B. sulphur(iii) oxide C. sulphur trioxide D. disulphur trioxide 9. What is the correct formula for the compound that contains magnesium and phosphate ions? A. MgP 4 B. Mg 3 P 4 C. Mg 2 (P 4 ) 3 D. Mg 3 (P 4 ) Which compound has no covalent bonds? A. Na 2 S 4 B. KCl C. KCl 3 D. CH 3 Cl 11. The name of PbS 3 is A. lead sulphur oxide B. lead sulphate C. lead(ii) sulphur oxide D. lead(ii) sulphite 12. What is the key difference between an ionic bond and a covalent bond?

23 CHAPTER 4 BLM 2-20 Atoms, Ions, and Compounds Goal Use this page to review your understanding of atoms, ions, and compounds. Circle the letter of the best answer. 1. Which statement best fits the currently accepted model of the atom? A. Electrons associated with specific energy levels surround the nucleus of an atom. B. An atom is a sphere of positive charge in which electrons are embedded. C. An atom is a small indivisible sphere. D. An atom has a nucleus surrounded by positively charged particles. 2. When metal atoms form ions in compounds, they tend to A. gain electrons and form positive ions B. lose electrons and form positive ions C. gain electrons and form negative ions D. lose electrons and form negative ions 3. An Al 3+ ion contains A. 13 electrons and 13 protons B. 10 electrons and 10 protons C. 10 electrons and 13 protons D. 13 electrons and 10 protons 4. What does the diagram on the right represent? A. a nickel ion B. a silicon atom C. a nickel atom D. an oxygen ion 5. If you were asked to draw electron Bohr diagrams for the following elements, which element would have a different number of occupied energy levels? A. Mg 2+ B. F C. Ne D. Cl 6. Which list includes only substances with no ionic bonds? A. N 2 4, HBr, LiCN B. C 2, NH 3, N 2 C. S 3, BaCl 2, 2 D. NaCl, CH 4, Al(H) 3

24 BLM 2-20 continued Use the following diagram to answer the next three questions. 7. Which unknown represents an element in the halogen family? A. A B. B C. C D. D E. E 8. Which unknown represents an element that can be classified as a metalloid, having properties of both metals and non-metals? A. A B. B C. C D. D E. E 9. An experiment shows that an unknown element does not easily lose or gain electrons. Which unknown represents this element? A. B B. C C. D D. E E. E 10. The reaction of solid copper(ii) oxide with hydrogen gas at high temperatures produces copper metal and water. Which chemical equation represents this reaction? A. Cu H 2 Cu + 2 H 2 B. Cu H 2 2 Cu + 2 H 2 C. Cu + H 2 Cu + H 2 D. Cu H 2 Cu + H 2

25 CHAPTER 4 BLM 2-21 Chemical Formulas Review Goal Use this worksheet to review chemical equations and formulas. Circle the letter of the best answer. 1. Which name and formula match correctly? A. magnesium fluoride, MgF 2 B. sodium sulphide, NaS C. aluminum iodide, Al(I 3 ) 3 D. iron(ii) oxide, Fe 2 2. Which is the formula for aluminum carbonate? A. AlC 3 B. AlC 3 C. Al 2 C 3 D. Al 2 (C 3 ) 3 3. Which of the following sets of coefficients will balance the following skeleton equation? AlCl 3 + K KCl + Al A. 1, 2, 1, 2 B. 2, 6, 6, 1 C. 1, 3, 3, 1 D. 1, 2, 3, 1 4. Write the chemical formula for each of the following. (a) potassium nitride (b) lithium oxide (c) iron(ii) sulphide (d) nickel(iii) bromide (e) copper(i) oxide (f) nitrogen dioxide (g) nickel(iii) carbonate (h) sodium phosphate (i) iron(iii) hydroxide (j) ammonium sulphate

26 BLM 2-21 continued 5. Write the name for each of the following compounds. (a) Pb 2 (b) CuCl (c) Fe 2 S 3 (d) Ni 3 (P 4 ) 2 (e) CuC 3 6. (a) Write the corresponding skeleton equation for the following word equation. calcium + water calcium hydroxide + hydrogen (b) Balance the skeleton equation. 7. Draw Lewis diagrams for each of the following covalent molecules. (a) carbon tetrachloride (b) magnesium fluoride 8. Balance each of the following skeleton equations. (a) HCl + Na 2 C 3 NaCl + H 2 + C 2 (b) Al(H) 3 + HCl AlCl 3 + H 2

27 CHAPTER 4 BLM 2-22 Chapter 4 Review Chart Goal Use this page to record your answers to questions 11 and 18 in Chapter 4 Review. What to Do Use these charts to record your answers to questions 11 and 18 on page 217 of your student book

28 CHAPTER 4 BLM 2-23 Chapter 4 Quiz Goal Check your understanding of Chapter 4. What to Do Circle the letter of the best answer. 1. Which subatomic particle(s) make up most of the mass of an atom? A. electrons B. neutrons C. electrons and protons D. neutrons and protons 2. Which statement best describes the diagram to the right? A. This is a Bohr diagram that shows eight neutrons. B. This is a Lewis diagram that shows eight neutrons. C. This is a Bohr diagram that shows ten neutrons. D. This is a Lewis diagram that shows ten neutrons. 3. Which statement best describes the following diagram? A. The pure substance is an element, and the line refers to a charge of 1. B. The pure substance is a compound, and the line refers to a charge of 1. C. The pure substance is an element, and the line refers to a pair of bonding electrons. D. The pure substance is a compound, and the line refers to a pair of bonding electrons. 4. What is the name of Pb 2? A. lead(ii) dioxide B. lead(iv) oxide C. lead dioxide D. phosphorus boron oxide 5. What is the correct formula for aluminum hydroxide? A. Al 3 H B. AlH 3 C. Al(H) 3 D. Al(H 3 )

29 BLM 2-23 continued 6. Which statement best describes (NH 4 ) 2 Cr 2 7? A. It is an ionic compound with 16 atoms in total. B. It is an ionic compound with 19 atoms in total. C. It is a covalent compound with 16 atoms in total. D. It is a covalent compound with 19 atoms in total. 7. What is the charge on the plutonium atom (Pu) in the compound Pu 2 5? A. 3+ B. 4+ C. 5+ D What are the coefficients, from left to right, that correctly balance the following equation? A. 1, 3, 2, 3 B. 1, 7, 2, 3 C. 2, 7, 4, 6 D. 2, 3, 4, 6 9. What are the coefficients, from left to right, that correctly balance the following equation? A. 3, 4, 12, 1 B. 3, 3, 6, 1 C. 6, 3, 4, 2 D. 6, 4, 2, Which statement best describes the following equations? I. II. A. I is a word equation, and II is a skeleton equation. B. I is a skeleton equation, and II is a balanced equation. C. I is a balanced equation, and II is a word equation. D. I is a skeleton equation, and II is a word equation.

30 BLM 2-23 continued Match the Term on the left with the best Descriptor on the right. Each Descriptor may be used only once. Term 11. binary covalent compound 12. polyatomic ion 13. ionic compound 14. element 15. atomic number 16. reactant Descriptor 3 A. P 4 B. Br 2 C. substance made during a reaction D. equal to the number of protons in an atom E. CH 4 F. substance consumed during a reaction G. MgCl 2 H. equal to the number of neutrons in an atom Short Answer Questions 17. (a) Draw a Lewis diagram representing ammonia (NH 3 ). (b) Draw a Bohr diagram representing Mg. 18. Write the formula or name of the following compounds. (a) iron(iii) chloride (b) ammonium phosphate (c) dinitrogen trisulphide (d) P 4 10 (e) Na 2 S Balance the following equations. (a) KI + AlCl 3 KCl + AlI 3 (b) C 3 H C 2 + H 2 Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

31 CHAPTER 5 Chemical Reactions in ur BLM 2-24 Everyday Lives Goal In a group assignment, investigate chemical reactions that affect our daily lives. What to Do 1. Your group will be assigned one topic from the following list. 2. You will be given a total of three class periods to research, prepare information, and present the topic to your class. 3. During this time, your group is to prepare the following. (a) A one- to two-page, word-processed report on the assigned topic. This report will be photocopied and handed out to your classmates. Labelled diagrams can be included. (b) A colourful poster that will be displayed in the classroom. (c) A presentation to the class. This will occur in the third period allotted to this assignment. Use of originality, video cameras, computer graphics, and so on is encouraged. Topics What are the acid-base chemical reactions involved in the following? 1. Film processing 2. Food processing 3. Fabric dyeing 4. Hair dyeing 5. Agriculture 6. Wine-making 7. The pulp and paper industry 8. Mineral processing Assessment 1. Student handout mark 2. Poster mark 3. Presentation mark

32 CHAPTER 5 BLM 2-25 Acids and Bases Goal Demonstrate your understanding of acids and bases. What to Do 1. Use the following terms and symbols to complete the sentences below. Some terms and symbols will be used more than once, and some not at all. H + H conduct lower sour bitter + NH 4 sweet red blue greater than less than turns pink remains colourless orange higher do not conduct (a) Acids are substances that dissolve in water to release ions. Acids are characterized by a ph value 7. The the ph value, the more acidic a solution is. When an acid is added, litmus turns a colour and phenolphthalein. Acidic solutions electricity. Acids are responsible for the taste in foods. (b) Bases are substances that dissolve in water to release ions. Bases are characterized by a ph value 7. The the ph value, the more basic a solution is. When a base is added, litmus turns a colour and phenolphthalein. Basic solutions electricity. Bases are responsible for the taste in foods. 2. Complete the following table about acids and bases. The first row has been completed as an example. Name of Substance Chemical Formula of Aqueous Solution Name of Acid or Base hydrogen sulphide H 2 S hydrosulphuric acid magnesium hydroxide hydrogen chlorate H 2 C 3 NH 4 H CH 3 CH phosphoric acid sulphurous acid

33 CHAPTER 5 BLM 2-26 Working with Acids and Bases Goal Demonstrate your understanding of the concepts, procedures, and safety precautions for using acids and bases. What to Do 1. Explain why each item is necessary for an activity that involves acids and bases. Show your knowledge of the properties of acids and bases in your answers. (a) Safety glasses (b) Gloves (c) Lab apron (d) Eyewash station (e) Safety shower 2. What property of baking soda makes it useful for cleaning up acid spills and base spills? 3. A student has spilled some acid onto his hand. Another student suggests the first student should apply a basic solution containing hydroxide ions to neutralize the hydrogen ions. (a) Explain why it is not a good idea to attempt to neutralize the acid on the student s hand. (b) What should the first student do instead?

34 CHAPTER 5 Salts, and Metal and Non-Metal BLM 2-27 xides Goal Demonstrate your understanding of salts and metal and non-metal oxides. What to Do 1. Salts are a class of compounds that include ionic compounds. Salts can be produced when an acid and a base react. Complete and balance the following neutralization reactions. Then, write the name of the salt produced in each reaction. (a) HBr + NaH Name of salt: (b) H 2 S 4 + Mg(H) 2 Name of salt: (c) H 3 P 4 + Sr(H) 2 Name of salt: (d) HN 3 + Al(H) 3 Name of salt: (e) CH 3 CH + Ca(H) 2 Name of salt: 2. Metals can react with acids to produce a salt as well as hydrogen gas. Complete and balance the following reactions of a metal with an acid. In each case, hydrogen gas and a salt will be produced. Write the name of the salt produced in each reaction. (a) HF + Mg (b) HCl 3 + Al (c) H 3 P 3 + Cu (d) HN 3 + Ca (e) CH 3 CH + Zn Name of salt: Name of salt: Name of salt: Name of salt: Name of salt: 3. Metal oxides react with water to make solutions that are basic. Non-metal oxides react with water to produce solutions that are acidic. For each oxide, predict whether dissolving it in water will make the solution acidic or basic. (a) Mg (b) S 2 (c) P 4 10 (d) Na 2

35 CHAPTER 5 BLM 2-28 Classifying Substances Goal Use this page to practise classifying substances. What to Do Complete the following charts. 1. A group of students is given four containers, labelled A, B, C, and D. The students assemble the following list of characteristics for the four unknown substances. The students know that one of the substances is an acid, one is a base, one is covalent, and one is ionic. Classify each substance. Substance State at Room Temperature Litmus Paper Test Conductivity Test Classification A Liquid Red turns blue Conducts B Solid No change when B dissolved in water Conducts when dissolved in water C Liquid No change Does not conduct D Gas Blue turns red when D bubbled through water Conducts when bubbled through water 2. The students are told that the substances are methanol, hydrogen sulphide, aqueous ammonium sulphide solution, and aqueous sodium hydroxide solution. In the following table, write the chemical formula for each substance and the letter that corresponds to the substance. methanol Substance hydrogen sulphide sodium hydroxide (aqueous solution) ammonium sulphide (aqueous solution) Chemical Formula Substance Letter (A, B, C, or D)

36 CHAPTER 5 BLM 2-29 Acids and Bases Review Goal Use this page to review your understanding of acids, bases, and salts. What to Do Circle the letter of the best answer. 1. What are substances with a ph above 7 considered to be? A. basic B. acidic C. salty D. neutral 2. Which is not a characteristic of acids? A. bitter taste B. turn litmus red C. react with bases to form salts D. react with active metals to form H 2 gas 3. Four compounds are dissolved in water. Which of the resulting solutions (A to D) are good conductors of electricity? I H 2 C 3 II NH 4 H III CH 3 H IV NaCl A. I, II, and III only B. I and III only C. II and IV only D. I, III, and IV only 4. Which of the following is a property of a base? A. It has a sour taste. B. It turns litmus paper red. C. It tastes bitter. D. It has a ph less than Solution A has a ph of 4, and Solution B has a ph of 6. How many times more acidic is Solution A than Solution B?

37 CHAPTER 5 BLM 2-30 Careers in Chemistry Goal Gain an understanding of the chemistry-related careers. What to Do From the list below, select one of the careers in chemistry that interests you. Since this is not an exhaustive list, after some research, you might select another career choice that interests you. btain your teacher s permission first if you wish to report on a different career. Write a one-page, word-processed report on the career of your choice. Use the following subheadings as a guide for your report. 1. Career Description (nature of the job, type of work done, etc.) 2. Minimum Education Required 3. Salary Expectations 4. ther (for example, career advancement, possible promotions, etc.) Careers in Chemistry Analytical chemist Biochemist Chemical engineer Chemical engineering technologist Cosmetic chemist Criminology chemist or technologist Dialysis technician or technologist Enological chemist Environmental chemist Environmental technologist Fingerprint technician Food chemist Food technologist Forensic technician Forestry technologist Hematology technologist Inorganic chemist Medical technologist phthalmic laboratory technician ptical laboratory technician rganic chemist Pharmaceutical chemist Pharmacist Pharmacologist Pharmacy assistant Pollution control chemist Pollution control technologist Polymer chemist Quality control chemist Quality control technician Research assistant Research chemist Science (chemistry) teacher Soil chemist Soil science technologist Technical sales Technical writer Textile chemist Toxicologist Water resources technologist

38 CHAPTER 5 BLM 2-31 Chapter 5 Quiz Goal Check your understanding of Chapter 5. What to Do Circle the letter of the best answer. You may refer to a periodic table, ion chart, ph scale, and ph indicator colour change chart. 1. Which of the following household items is basic? A. baking soda B. grapes C. bananas D. water 2. What are the colours of methyl red indicator and bromothymol blue indicator in separate samples of water at ph 7? A. Methyl red indicator is red, and bromothymol blue indicator is yellow. B. Methyl red indicator is yellow, and bromothymol blue indicator is blue. C. Methyl red indicator is yellow, and bromothymol blue indicator is green. D. Methyl red indicator is orange, and bromothymol blue indicator is green. 3. Which are properties characteristic of an acid but not a base? A. sour, reacts with magnesium, turns litmus blue B. bitter, reacts with magnesium, turns litmus red C. slippery touch, does not react with magnesium, turns litmus blue D. sour, turns phenolphthalein indicator colourless, turns litmus red 4. What the best chemical definition of a salt? A. a material found by evaporating sea water B. a material formed by the reaction of an acid with a base C. a material containing a metal ion and an oxide ion D. a material containing a metal ion and carbonate ion 5. Burning magnesium in air produces a brilliant white flame and a white powder. When the white powder is placed in water, it dissolves. What is the colour when bromothymol blue indicator is added to this solution? A. colourless B. yellow C. green D. blue

39 BLM 2-31 continued 6. What is formed when HCl and NaH solutions are combined? A. NaCl and H 2 B. NaH and ClH C. NaCl and H 2 D. There is no reaction. 7. Which list shows the elements that are the most reactive towards water on the left and least reactive towards water on the right? A. cesium, magnesium, potassium B. cesium, potassium, magnesium C. potassium, cesium, magnesium D. magnesium, potassium, cesium 8. Which of the following compounds are organic? I Na 2 C 3 II CH 3 CH 2 CH 3 III CH 3 H A. I and II only B. II and III only C. I, II, and III D. None of these compounds is organic. 9. Consider the two representations of ethane. What kind of representation is each? A. The left is a molecular formula, and the right is a structural formula. B. The left is a structural formula, and the right is a molecular formula. C. The left is a ball-and-stick formula, and the right is a space-filling model. D. The left is a space-filling model, and the right is a ball-and-stick model. 10. Which of the following is true of the element carbon? I II Carbon can form four bonds. Carbon atoms can combine to form long chains. A. I only B. II only C. Both statements are true. D. Neither statement is true.

40 BLM 2-31 continued Match the Term on the left with the best Descriptor on the right. Each Descriptor may be used only once. Term 11. indigo carmine 12. inorganic 13. solvent 14. acid 15. concentration 16. ph scale Descriptor A. releases H - ions in solution B. compounds that do not contain carbon C. releases H + ions in solution D. acid-base indicator E. a set of numbers that measure acidity levels F. a liquid capable of dissolving other substances G. turns red in acid H. a measure of the quantity of a substance dissolved in a given volume Short Answer Questions 17. Name the following compounds and indicate whether each is an acid, a base, or neither. Compound Name Acid, Base, or Neither? (a) H 2 S 4 (b) HCl (c) Ca(H) Complete the following chart. Indicator Colour at ph 4 Colour at ph 7 Colour at ph 10 Blue litmus paper Red litmus paper 19. Complete and balance the following equations. (a) HBr + KH KBr + (b) H 2 S 4 + Al(H) 3 + (c) The reactions in (a) and (b) are both of the same type. What is the name of this type of reaction? Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

41 CHAPTER 6 Chemical Changes and Physical BLM 2-32 Changes Goal Demonstrate your ability to distinguish between chemical and physical changes. What to Do Classify each change in the following table as either chemical or physical. Explain your classification. Change Chemical or Physical? Explanation A sheet of paper is crumpled into a ball. A sheet of paper is set on fire and burns to ashes. Steel wool is placed in a glass of salty water. The steel wool rusts. A sheet of flexible, colourless plastic is left outside, in bright sunlight, and becomes yellow and brittle over time. A teaspoon of white sugar (sucrose) dissolves in a glass of warm water. Vinegar is poured over a teaspoon of baking soda. The white baking soda powder fizzes, and bubbles form. A red-hot nail is inserted into a large block of ice. Steam is formed as the nail contacts the block, and water flows away from the nail.

42 CHAPTER 6 BLM 2-33 Endothermic and Exothermic Goal Review your understanding of endothermic and exothermic reactions. What to Do Read the following summary of exothermic and endothermic reactions. Then, answer the questions on the next page. Summary A chemical change is always accompanied by a change in energy because the atoms or ions that make up the reactants are rearranged. During a reaction, chemical bonds that hold the reactant atoms or ions together must be broken and new chemical bonds must be formed within the product substance(s). The breaking of chemical bonds requires the input of energy and is defined as an endothermic process. The formation of chemical bonds releases energy and is defined as an exothermic process. Since any chemical change involves both the breaking and formation of chemical bonds, there are two possible outcomes of any chemical change. The overall change is exothermic if more energy is released to form the product chemical bonds than is required to break the reactant chemical bonds. The overall change is endothermic if less energy is released to form the product chemical bonds than is required to break the reactant chemical bonds. The energy that is released or absorbed is related to the external environment of the chemical reaction. Endothermic reactions absorb thermal energy from the surrounding environment and result in a decrease in temperature. Exothermic reactions, on the other hand, release thermal energy to the surrounding environment and result in an increase in temperature. Type of Reaction Breaking Chemical Bonds (Reactants) Forming Chemical Bonds (Products) verall Energy Change Exothermic Energy released Endothermic Energy absorbed

43 BLM 2-33 continued 1. Classify each reaction as either endothermic or exothermic, and briefly explain your answer. Description of Chemical Reaction A piece of paper is ignited and burns with a bright flame. Pentaborane (a colourless liquid), B 5 H 9, reacts violently with oxygen gas to form solid diborane, B 2 3, and water, typically bursting into flame and often exploding. Pure iron metal is formed and carbon dioxide is released when iron(iii) oxide ore is heated to a very high temperature in the presence of solid carbon. Sodium hydroxide solution and hydrochloric acid solution are mixed. The temperature of the mixture increases. Mixing ammonium thiocyanate and barium hydroxide octahydrate in a beaker causes water on the outside of the beaker to freeze. Endothermic or Exothermic? Explanation 2. A student claims that the reaction of butane gas and oxygen gas must be endothermic since a spark is needed to ignite the butane gas in a lighter. Do you agree or disagree with this claim? Explain your answer.

44 CHAPTER 6 BLM 2-34 Synthesis Reaction Equations Goal Use this page to practise balancing synthesis reaction equations. What to Do 1. Balance each equation for a synthesis reaction. (a) K + 2 K 2 (b) P 4 + Cl 2 PCl 5 (c) Cu + S 8 CuS (d) Mg + 2 Mg (e) Fe + 2 Fe 2 3 (f) P 4 + S 8 P 2 S 5 (g) C + 2 C (h) N N 2 (i) Li + N 2 Li 3 N (j) S S 2 2. Write a balanced chemical equation to represent each reaction described below. (a) Aluminum metal reacts with oxygen to form aluminum oxide. (b) Metallic zinc combines with sulphur to form zinc sulphide.

45 CHAPTER 6 Decomposition Reaction BLM 2-35 Equations Goal Use this page to practise balancing decomposition reaction equations. What to Do 1. Balance each equation for a decomposition reaction. (a) NaCl Na + Cl 2 (b) CaBr 2 Ca + Br 2 (c) CCl 4 C + Cl 2 (d) NCl 3 N 2 + Cl 2 (e) P 4 10 P (f) Ag 2 Ag + 2 (g) HCl H 2 + Cl 2 (h) KI K + I 2 (i) AlCl 3 Al + Cl 2 (j) Cu Cu Write a balanced chemical equation to represent each reaction described below. (a) Rubidium oxide decomposes into its elements. (b) Calcium chloride decomposes into its elements.

46 CHAPTER 6 Single Replacement Reaction BLM 2-36 Equations Goal Use this page to practise balancing single replacement reaction equations. 1. Balance each equation for a single replacement reaction. (a) K + H 3 P 4 K 3 P 4 + H 2 (b) Fe + H 2 S Fe 2 S 3 + H 2 (c) Cl 2 + MgBr 2 MgCl 2 + Br 2 (d) Cu + Ag 2 C 3 CuC 3 + Ag (e) Br 2 + KI I 2 + KBr (f) Mg + Zn 3 (P 4 ) 2 Mg 3 (P 4 ) 2 + Zn (g) K + Al(N 3 ) 3 Al + KN 3 (h) Ca + H 2 Ca(H) 2 + H 2 (i) Na + H 2 S 4 Na 2 S 4 + H 2 (j) K + H 2 KH + H 2 2. Write a balanced chemical equation to represent each reaction described below. (a) Silver reacts with gold(iii) nitrate. (b) Copper reacts with lead(ii) sulphate.

47 CHAPTER 6 Double Replacement Reaction BLM 2-37 Equations Goal Use this page to practise balancing double replacement reaction equations. What to Do 1. Balance each equation for a double replacement reaction. (a) Na 2 S 4 + BaCl 2 BaS 4 + NaCl (b) HN 3 + Ba(H) 2 H 2 + Ba(N 3 ) 2 (c) Na 2 C 3 + Fe(N 3 ) 3 Fe 2 (C 3 ) 3 + NaN 3 (d) CaCl 2 + K 3 P 4 Ca 3 (P 4 ) 2 + KCl (e) Al 2 (S 4 ) 3 + Ba(H) 2 Al(H) 3 + BaS 4 (f) NaH + H 2 S 4 H 2 + Na 2 S 4 (g) Na 3 P 4 + Ag 2 S 4 Na 2 S 4 + Ag 3 P 4 (h) Na 2 Cr 4 + Cu(N 3 ) 2 NaN 3 + CuCr 4 (i) H 3 P 4 + KH H 2 + K 3 P 4 (j) Na 2 C 3 + HN 3 H 2 C 3 + NaN 3 2. Write a balanced chemical equation to represent each reaction described below. (a) Solutions of sodium hydroxide and hydrochloric acid react. (b) A silver nitrate solution reacts with a sodium chloride solution.

48 CHAPTER 6 BLM 2-38 Combustion Reaction Equations Goal Use this page to practise balancing combustion reaction equations. What to Do 1. Balance each equation for a combustion reaction. (a) C 2 H C 2 + H 2 (b) C 3 H C 2 + H 2 (c) C 6 H C 2 + H 2 (d) C 8 H C 2 + H 2 (e) C 2 H C 2 + H 2 (f) C 2 H C 2 + H 2 (g) C 2 H C 2 + H 2 (h) C 6 H C 2 + H 2 (i) CH C 2 + H 2 (j) C 2 H 5 H + 2 C 2 + H 2 2. Write a balanced chemical equation to represent each reaction described below. (a) Candle wax, C 25 H 52, is burned to produce carbon dioxide and water. (b) Sucrose, C 12 H 22 11, is burned to produce carbon dioxide and water.

49 CHAPTER 6 Classifying and Balancing BLM 2-39 Equations Goal Use this page to practise classifying and balancing reactions. What to Do Classify each reaction as a synthesis (S), decomposition (D), single replacement (SR), double replacement (DR), or combustion (C) reaction. Then, balance each equation. Reaction Classification 1. Li + AlCl 3 Al + LiCl 2. NH 3 N 2 + H 2 3. K + Br 2 KBr 4. C 10 H C 2 + H 2 5. NH 4 H + H 2 C 3 H 2 + (NH 4 ) 2 C 3 6. H 2 H Al + Cl 2 AlCl 3 8. Zn + SnF 4 Sn + ZnF 2 9. Ni + HCl NiCl 2 + H Au(CN) 3 + Zn Au + Zn(CN) Be Be 12. FeCl 3 + Na 2 S 3 NaCl + Fe 2 (S 3 ) C 8 H C 2 + H (NH 4 ) 2 S + Mn(N 3 ) 2 NH 4 N 3 + MnS 15. P 4 + F 2 PF Al 2 (S 4 ) 3 + Na 3 P 4 Na 2 S 4 + AlP C 2 + H 2 C 6 H H 3 (P 4 ) + Cu(H) 2 H 2 + Cu 3 (P 4 ) 2

50 CHAPTER 6 BLM 2-40 Chemical Reactions Review Goal Review your understanding of chemical reactions. 1. Butane gas, C 4 H 10, is mixed with pure oxygen. The mixture is ignited and burns. (a) Write the balanced chemical equation to represent the reaction. (b) Explain how the law of conservation of mass is illustrated by the reaction. 2. A solution of calcium hydroxide reacts with sulphuric acid to produce water and calcium sulphate. (a) Write a balanced chemical equation to represent the reaction. (b) Classify the reaction as a synthesis, decomposition, single replacement, double replacement, or combustion reaction. 3. (a) Classify the following reaction. HN 3 + NaH H 2 + NaN 3 (b) Name each of the reactants and products.

51 CHAPTER 6 BLM 2-41 Types of Reactions Review Goal Review the types of chemical reactions. Circle the letter of the best answer. 1. Sn + 2Cl 2 SnCl 4 What kind of chemical reaction is this? A. synthesis reaction B. decomposition reaction C. replacement reaction D. double replacement reaction 2. Which of the following is an example of a single replacement reaction? A. Al(N 3 ) 3 + Fe(Cl 3 ) 3 Al(Cl 3 ) 3 + Fe(N 3 ) 3 B. 2Al(N 3 ) 3 + 3Cu 3Cu(N 3 ) 2 + 2Al C. 2Ag 2 C 3 2Ag 2 + 2C 2 D. N H 2 2HN 3 Short Answer Questions 3. What is the difference between the following? (a) a single and a double replacement reaction (b) a synthesis and a decomposition reaction 4. Complete and balance the following neutralization reaction. NaH + H 2 S 4 5. (a) Complete the following reaction. Cu + 2AgN 3 (b) Identify the type of reaction. 6. (a) Complete the following reaction Ba(H) 2 + Na 2 S 4 (b) Identify the type of reaction.

52 CHAPTER 6 BLM 2-42 Chapter 6 Quiz Goal Check your understanding of Chapter 6. What to Do Circle the letter of the best answer. You may refer to a periodic table and an ion chart. 1. What type of reaction is the following? silver + gold(iii) nitrate silver nitrate + gold A. synthesis B. neutralization C. single replacement D. double replacement 2. What type of reaction is the following? C 3 H C 2 + 4H 2 A. single replacement B. combustion C. decomposition D. double replacement 3. Classify the reaction type and predict the products of the following reaction. HCl + Mg(H) 2? A. double replacement; products are MgCl and H(H) 2 B. double replacement; products are MgCl 2 and H 2 C. neutralization; products are MgCl and H(H) 2 D. neutralization; products are MgCl 2 and H 2 4. Which of the following reactions is double replacement? A. Pb + 2CuCl 2 PbCl 2 + 2Cu B. Na 2 C 3 + CaBr 2 CaC 3 + 2NaBr C. MgC 3 + 2HBr MgBr 2 + C 2 + H 2 D. Mg(H) 2 + 2HBr MgBr 2 + 2H 2 5. What are the products in the decomposition reaction involving aluminum oxide? A. Al and B. Al 2 3 C. Al and 2 D. Al

53 BLM 2-42 continued 6. In order to start a campfire, wood is chopped into many small pieces, called kindling. Which factor makes it easier to light a fire using kindling instead of large pieces of wood? A. temperature B. concentration C. surface area D. catalyst 7. When hydrogen gas is mixed with oxygen gas in a closed container, both gases mix but no noticeable reaction takes place. When a piece of platinum metal is placed in the gas mixture, the mixture suddenly explodes. After the explosion, analysis shows that the amount of platinum metal did not change during the explosion. What factor is responsible for the onset of the explosion? A. The concentration of the oxygen was high. B. The concentration of the hydrogen was high. C. The platinum was a reactant. D. The platinum was a catalyst. 8. The chain on a bicycle rusts faster when the bicycle is left outside in damp conditions. Which of the following factors affect the rate at which the bicycle chain rusts? I II III The surface area of the metal in the chain The concentration of oxygen in the air The temperature A. I only B. II and III only C. III only D. I, II, and III 9. A zinc metal strip is placed in hydrochloric acid. Which of the following changes could be made to decrease the rate of this reaction? I II III IV Add water to dilute the hydrochloric acid. Place the beaker on a hot plate in order to raise the temperature. Add a catalyst. Change the shape of the magnesium to make it thicker and less wide. A. I and II only B. II and III only C. I and IV only D. II and IV only

54 BLM 2-42 continued 10. Suppose a chemist performed an experiment by dissolving equal masses of calcium carbonate in separate beakers containing sulphuric acid. The results of three trials are shown in the table below. Trial Sulphuric Acid Calcium carbonate Temperature 1 Concentrated Finely ground 10 o C 2 Concentrated Lump 10 o C 3 Dilute Lump 15 o C Trial 1 was the fastest, and Trial 2 was the slowest. Which of the following correctly lists the factors from most important to least important in increasing the rate of this reaction? A. concentration, surface area, temperature B. temperature, surface area, concentration C. surface area, concentration, temperature D. surface area, temperature, concentration Match the Term on the left with the best Descriptor on the right. Each Descriptor may be used only once. Term 11. synthesis 12. precipitate 13. combustion 14. surface area 15. neutralization 16. catalyst Descriptor A. a reaction in which a compound splits into two elements B. the reaction involving a burning candle C. the reaction of an acid with a base D. a solid that forms when two ionic solutions are mixed E. a substance that increases reaction rate without being used up by the reaction F. affects the rate of a reaction between a solid and a liquid G. a reaction in which two elements combine to form a compound Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

55 BLM 2-42 continued Short Answer Questions 17. Identify each of the following descriptions as synthesis, decomposition, single replacement, double replacement, neutralization, or combustion. (a) There is only one reactant. (b) ne reactant is an element. The other is a compound. (c) Two ionic compounds react to form two new ionic compounds. 18. Which of the four factors affecting reaction rate is most important in each question below? Choose from among concentration, temperature, surface area, and catalyst. (a) Dust in a granary explodes when it comes in contact with a spark. (b) Table sugar is digested in the mouth when it dissolves in saliva, which contains a digestive enzyme. (c) A person blows on a fire to help get it burning better. 19. Complete and balance each of the following equations. Then classify each reaction type. (a) Zn + Cu(H) 2 Reaction type: (b) C 2 H Reaction type: (c) Al + S 8 Reaction type:

56 CHAPTER 7 BLM 2-43 Isotopes and Ions Goal Demonstrate your understanding of isotopes and ions. What to Do Answer each question in the space provided. 1. Complete the following table by filling in the missing information about ions. Name of Ion Symbol Number of Protons Number of Electrons Ion Charge lithium ion chloride ion Mg I Se 2 scandium ion Al calcium ion phosphide

57 BLM 2-43 continued 2. Complete the following table by filling in the missing information about isotopes. The first row is completed as an example. Name of Isotope Symbol Mass Number Number of Protons Number of Neutrons hydrogen H scandium-49 nitrogen Co U I carbon Although oxygen-16 is the most common isotope of oxygen, oxygen-17 and oxygen-18 are also present. Despite the differences in the atomic structures of the three isotopes, there is no difference in how they form ionic or covalent compounds with atoms of other elements. Explain how this can be.

58 CHAPTER 7 BLM 2-44 Isotopes Goal Use this page to show your understanding of isotopes. Circle the letter of the best answer. 1. What do two isotopes of an element have? A. the same number of electrons but a different number of protons B. the same number of neutrons but a different number of protons C. the same number of protons, electrons, and neutrons D. the same number of protons but a different number of neutrons 2. What does a sodium-23 isotope contain? A. 11 protons and 12 neutrons B. 11 protons and 23 neutrons C. 12 protons and 11 neutrons D. 23 protons and 23 neutrons 3. Isotopes are two atoms of the same element that do which of the following? A. become electrically charged B. differ in mass but are chemically alike C. give away electrons to become positively charged D. have the same mass but different chemical properties 4. Which of the following describes the isotope Ca? A. 40 protons and 20 neutrons B. 20 protons and 40 neutrons C. 20 protons and 20 neutrons D. 40 electrons and 20 neutrons Use the following information to answer the next two questions. The nuclear notations for four mystery elements are shown below. 56 AA 60 BB 60 CC 58 DD How many subatomic particles does mystery element AA have? A. 26 protons, 26 neutrons, and 26 electrons B. 26 protons, 30 neutrons, and 26 electrons C. 30 protons, 26 neutrons, and 30 electrons D. 26 protons, 56 neutrons, and 30 electrons 6. Which mystery elements are isotopes of the same element? A. AA and BB B. BB and CC C. CC and DD D. AA and DD

59 CHAPTER 7 Modelling Rates of Radioactive BLM 2-45 Decay Goal Use this page to record your data for Find ut Activity 7-2A, Modelling Rates of Radioactive Decay. What to Do Use this chart to record your data for Find ut Activity 7-2A, Modelling Rates of Radioactive Decay, on page 303 of your student book.

60 CHAPTER 7 Half-Life and Radioisotope BLM 2-46 Dating Goal Demonstrate your understanding of the use of half-life in radioisotope dating. What to Do Answer the questions in the space provided. 1. Examine the graph showing the decay curve for carbon-14. The graph shows the amount of radioactive carbon-14 that would be in a sample of organic material for years after the organism died. (a) Define half-life. (b) How long is one half-life for carbon-14? (c) What percentage of carbon-14 remains (i) after one half-life? (ii) after two half-lives? (iii) after three half-lives? (d) Use the graph to estimate the percentage of carbon-14 remaining after (i) 5000 years (ii) years (iii) years. (e) Use the graph to estimate the number of years that have passed since the organism died if the percentage of parent isotope that remains is (i) 40% (ii) 20% (iii) 5%. (f) Explain why carbon-14 half-life measurements are not effective in dating an organism that has been dead for more than years.

61 BLM 2-46 continued 2. Volcanic rocks can be dated using the potassium-40 clock, a dating method based on the decay of the potassium-40 isotope into the argon-40 isotope. Potassium-40 can exist as hot molten rock, whereas argon-40, the daughter isotope, escapes from the molten rock because it is a gas. When the molten rock solidifies, potassium-40 is present, but argon-40 is absent. The age of volcanic rock can be measured by comparing the amount of these two isotopes present in the rock. (a) Why is there no argon-40 present in the molten rock when it solidifies? (b) After many years, argon-40 is present in volcanic rock containing potassium-40, even though no argon-40 was there to begin with. How did the argon-40 get there? (c) What is the length, in years, of one half-life of potassium-40? (d) Suppose a sample of volcanic rock contained 100 nanograms (a nanogram is a billionth of a gram) of potassium-40 when the rock first formed. How many nanograms of potassium-40 and of argon-40 would be present in the sample after (i) 1 half-life? (ii) 2 half-lives? (iii) 3 half-lives?

62 BLM 2-46 continued 3. The table of parent-daughter isotopes shows three different isotope pairs that are used in radioisotope dating. Examine the chart and answer the following questions. (a) Lead-207 is called the daughter of uranium-235. What does this mean? (b) How old is a rock sample that contains uranium-235 and lead-207 in equal amounts? (c) The age of Earth was first established in 1953 when Claire C. Patterson of the California Institute of Technology used a uranium-lead clock to analyze rock. In comparing amounts of uranium-235 with lead-207, he established that slightly less than 8 half-lives of uranium-207 had passed since the rock formed. Using this data, estimate the age of Earth. (d) The rocks that make up the Canadian shield are extremely old. They are estimated to be between 3.7 and 3.8 billion years. (A billion is a thousand million). (i) Estimate how many half-lives of uranium-235 would have passed in a sample of rock this old. (ii) Estimate the percentage of original uranium that would remain in a sample of rock from the Canadian shield. (e) Suppose a sample of rock from the Canadian shield were analyzed using the potassium-40 clock. What information could this give about the age of rock? (f) Could carbon-14 dating be used to estimate the age of rocks in the Canadian shield? Explain. Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

63 CHAPTER 7 BLM 2-47 Chapter 7 Quiz Goal Check your understanding of Chapter 7. What to Do Circle the letter of the best answer. You may refer to a periodic table, an ion chart, and a common isotope pairs chart. 1. Which of the following is true of subatomic particles in a nucleus of vanadium-50? A. It has 23 protons and 27 neutrons. B. It has 23 protons and 28 neutrons. C. It has 27 protons and 23 neutrons. D. It has 27 protons and 51 neutrons. 2. Which of the following nuclear decay equations represent alpha decay? I 80Hg T1 + 0 β II 91Pa Ac + 4 He III 89 Ac Fr + 4 α 87 2 IV Ni A. I and IV only B. II and III only C. III and IV only D. I and III only 28 Ni γ 3. Consider the following partly completed nuclear decay equation. What is the symbol that correctly completes this equation? A. 14 C 6 B. 10 Be 4 C. 14 B 5 D. 14 N 7

64 BLM 2-47 continued 4. Refer to the Common Isotope Pairs Chart to determine the maximum effective dating range for carbon-14 dating. A. 14 years B years C years D years 5. Refer to the Common Isotope Pairs Chart to determine the age of a sample of rock that contains equal amounts of uranium-235 and lead-207. A. 355 million years B. 710 million years C billion years D. 4.5 billion years 6. Potassium-40 is a radioactive isotope with a half-life of 1.3 billion years. It has the daughter isotope argon-40. How old is a rock that is found to contain 1.0 g of potassium-40 and 3.0 g of argon-40? A billion years old B. 1.3 billion years old C. 2.6 billion years old D. 3.9 billion years old 7. Which nuclear symbol correctly completes the following nuclear reaction? A. 4 He 2 B. 92 Sr 37 C. 90 Sr 37 D. 143 Cs Which equation best represents the type of process that occurs in a CANDU reactor? A. C 7 H C 2 + 8H 2 + energy B. 1 n U Kr + Ba n + energy 56 0 C Ra Rn He + energy D. 2 H + 3 H 4 He n + energy

65 BLM 2-47 continued 9. Which of the following descriptions apply to the nuclear reactions that produce energy at the core of the Sun? I Heavy unstable nuclei split apart into two smaller nuclei. II Lightweight nuclei release energy when they join to form one nucleus. III The reaction produces products that are radioactive. A. I only B. II only C. I and III only D. II and III only 10. All of the following are concerns connected with the use of CANDU nuclear reactors. Three of these concerns are considered by nuclear regulators to be of very low risk because technologies and procedures have been implemented to deal with them. Which of these four concerns represents a problem for which no generally accepted solution has been reached? A. The nuclear reactor might have a runaway chain reaction and lead to a meltdown of the reactor core. B. The nuclear waste produced in the process might be stolen to produce nuclear weapons. C. The nuclear waste lasts millions of years and might leak out into the environment over time. D. Radioactive isotopes might be emitted during normal operation and harm people working at the facility and those living nearby. Match the Term on the left with the best Descriptor on the right. Each Descriptor may be used only once. Term Descriptor 11. beta particle 12. gamma radiation 13. mass number 14. daughter isotope 15. fusion 16. half-life A. high energy electromagnetic radiation B. a process involving the joining together of two nuclei C. a process involving the splitting of a large nucleus into smaller fragments D. the sum of the number of protons and neutrons in the nucleus of an atom E. the time it takes for one half of a sample of a radioisotope to decay F. a fast-moving electron that has been ejected from the nucleus of an atom G. a newly formed nucleus produced during a nuclear reaction H. a fast-moving helium nucleus that has been ejected from the nucleus of an atom Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

66 BLM 2-47 continued Short Answer Questions 17. Potassium-39 and potassium-40 are isotopes. Refer to the subatomic particles that make up the atoms of these isotopes. (a) How are these isotopes similar? (b) How are these isotopes different? (c) State which isotope is heavier than the other and explain why. 18. If 200 micrograms (or 200 billionths of a gram) of carbon-14 were present in a sample of pollen, how many grams would be left after the following periods? (a) 5730 years (b) years (c) four half-lives 19. Provide the nuclear symbol for the parent nucleus for each. (a) At (alpha decay) (b) Pu (beta decay) (c) 24 12Mg (gamma decay)

67 CHAPTER 7 BLM 2-48 Unit 2 Test Goal Check your understanding of Unit 2, Chemical Reactions and Radioactivity. 1. Which of the following is an ionic compound? A. F 2 B. CH 4 C. S 4 2 D. Na 3 P 4 Use the following Bohr diagram to answer questions 2 and Which of the following is represented by the diagram? A. argon atom B. silicon ion C. calcium ion D. calcium atom 3. How many valence electrons are indicated in the diagram? A. 2 B. 8 C. 10 D Ammonia window cleaner has a ph of 11. Which of the following shows the correct colour of each indicator when a small amount of ammonia window cleaner is tested? Methyl range Bromothymol Blue Indigo Carmine A. red blue blue B. red yellow green C. yellow green yellow D. yellow blue blue

68 BLM 2-48 continued 5. How many atoms of each of the following elements are indicated by the formula for ammonium sulphite? Nitrogen Hydrogen Sulphur xygen A B C D What is the name of the compound PbS 2? A. lead sulphide B. lead disulphide C. lead(ii) sulphide D. lead(iv) sulphide 7. Which of the following is an inorganic compound? A. Na 4 C B. C 2 H 6 C. C 12 H D. CH 3 CH 8. What type of reaction would you expect when potassium carbonate reacts with magnesium nitrate? A. single replacement B. double replacement C. neutralization D. combustion 9. When a flame is brought near a lump of coal, the coal slowly begins to burn. When the same flame is placed in the path of falling coal dust, an explosion occurs. What is the factor that causes the second reaction to have a faster rate of reaction? A. temperature B. catalyst C. concentration D. surface area 10. What element is formed during the alpha decay of uranium-235? A. thorium-231 B. neptunium-235 C. plutonium-239 D. protactinium-236

69 BLM 2-48 continued Match the Term on the left with the best Descriptor on the right. Each Descriptor may be used only once. Term 11. isotopes 12. fusion 13. covalent 14. organic 15. base 16. catalyst 17. half-life 18. non-metal oxide 19. salt 20. synthesis Descriptor A. a substance that increases reaction rate without being used up B. a nuclear reaction involving the splitting of atomic nuclei C. formed in the reaction of an acid and a base D. produces hydrogen ions in water E. a kind of chemical bond in which electrons are shared F. the time it takes half the a sample of a radioactive substance to decay G. main type of nuclear reaction that occurs in the Sun H. atoms of the same element that differ in number of neutrons I. type of chemical reaction that has one product J. produces hydroxide ions in water K. produces an acidic solution when dissolved in water L. compounds containing carbon Short Answer Questions 21. Complete the chart. Name of Isotope Symbol Mass Number Number of Protons Number of Neutrons scandium Co 7 8 Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

70 BLM 2-48 continued 22. Complete the chart. Name of Ion Symbol oxide ion 2 Number of Protons Number of Electrons Net Charge iodide ion 1 scandium ion Complete the chart. Name Formula Ionic or Covalent? lithium iodide carbon dioxide strontium hydroxide 24. Complete the chart. K 2 S Formula Name Ionic or Covalent? CuBr 2 S Consider the two drawings of a propane molecule in which the darker spheres represent carbon atoms and the lighter spheres represent hydrogen atoms. (a) Write the chemical formula for propane. (b) Is propane an organic or an inorganic compound? (c) Write a balanced chemical reaction showing the combustion of propane.

71 BLM 2-48 continued 26. Balance each reaction and classify as synthesis, decomposition, single replacement, double replacement, neutralization, or combustion. (a) Reaction Ni(H) 2 + HCl NiCl 2 + H 2 Classification (b) Au(CN) 3 + Zn Au + Zn(CN) 2 (c) 2 + Be Be 27. Sodium metal reacts with oxygen gas to produce sodium oxide. (a) Which type of chemical reaction is this? (b) Write the balanced chemical equation to represent the reaction. (c) Explain how the law of conservation of mass is illustrated by the reaction. 28. Zinc metal reacts with hydrochloric acid. (a) Predict the two products of the reaction. (b) Suggest two ways to increase the rate of this reaction. 29. Complete each equation by writing the correct nuclear symbol in the blank. Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

72 BLM 2-48 continued 30. Argon is a gas, and is driven out of molten rock, such as lava. Potassium however, remains in molten rock. Consider the following data for the isotope pairs potassium-40 (parent) and argon-40 (daughter). Explain how you would determine the age of a rock sample using potassium-40/argon-40 ratios.

73 CHAPTER 7 BLM 2-49 Visualizing Key Ideas Goal Use this page to record your answers to questions 1 and 33 from Unit 2 Review. What to Do Use these charts to record your answers to questions 1 and 33 from Unit 2 Review on pages 332 and 334 of your student book

74 UNIT 2 BLM 2-50 Unit 2 BLM Answers BLM 2-3, Interpreting an MSDS 1. (a) The name of the substance is cupric sulphate pentahydrate. The chemical formula is CuS 4 5H 2. (b) The substance is potentially toxic either by absorption or by inhalation. (c) To avoid exposure, students should wear safety glasses, an apron, and gloves. Although not stated, proper ventilation is essential. The dust should not be inhaled. (d) Excess amounts of this chemical should be deposited in a labelled waste container. (e) The teacher should be informed immediately. The teacher should immediately contact poison control or medical personnel to find out how to proceed. It is likely that vomiting will need to be induced. 2. Note: For this question, search the Internet to find MSDS sheets to give your students. Use a search engine to search for an MSDS for any chemical by typing in MSDS and the name of the chemical. You may wish to provide all students with copies of the same MSDS, or provide a variety of MSDS sheets. Answers are given below for an MSDS for strontium nitrate, Sr(N 3 ) 2. (a) The name of the substance is strontium nitrate. The chemical formula is Sr(N 3 ) 2. (b) The substance is slightly dangerous to your health. It may cause irritation of the skin, eyes, lungs, or gastrointestinal tract. Long-term exposure may result in liver, kidney, bone, blood, and nerve damage. (c) Inhalation of the dust from the chemical should be avoided. Students should wear gloves, goggles, and aprons. The substance must not be mixed with a reducing agent, because this could cause a fire. (d) In the event of a fire, firefighters should wear full protective clothing and a self-contained breathing apparatus. (e) All sources of ignition should be removed and proper ventilation should be initiated. Cleaning precautions should be taken to minimize or avoid dispersion of dust into the air. Waste should be sent to an appropriate hazardous waste facility. (f) The material should be stored in a cool, dry location. BLM 2-8, Periodic Table Scavenger Hunt 1. (a) niobium, Nb (b) bromine, Br (c) francium, Fr (d) technetium, Tc (e) tellurium, Te (f) beryllium, Be (g) xenon, Xe 2. Answers are in boldface. Name of Element Atomic Number Number of Protons Number of Electrons silicon oxygen chromium sodium aluminum potassium Copyright 2008, McGraw-Hill Ryerson Limited, a Subsidiary of the McGraw-Hill Companies. All rights reserved.

75 BLM 2-50 continued 3. BLM 2-9, Understanding Lewis Diagrams 1. Answers are in boldface. Name of Element Period Number Group Number Number of Energy Levels Number of Valence Electrons helium aluminum oxygen strontium silicon barium BLM 2-10, Bohr Diagrams and Lewis Diagrams Name of Element Bohr Diagram Lewis Diagram carbon oxygen