Science 14 Unit A: Investigating Properties of Matter Chapter 2 Pure Substances: Elements & Compounds pp WORKBOOK Name:

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1 Science 14 Unit A: Investigating Properties of Matter Chapter 2 Pure Substances: Elements & Compounds pp WORKBOOK Name:

2 Read pp Putting the Pieces Together pp The Periodic Table Element contains only one kind of atom pure substance o substance cannot be broken down into other substances atoms are the smallest bit of matter o Example: water (H 2 0) is the combination of two hydrogen atoms and one oxygen atom Dmitri Mendeleev developed the first periodic table o All elements known at the time were organized into groups with similar properties to create a chart, which was used to predict other undiscovered elements that were later added o Scientific technique and apparatus advances clarified Mendeleev s data and new elements discovered matched predicted properties almost perfectly o There are 118 known elements on the table today Periodic tables may look different, but they all consistently o look like a chart o include information about one element in each square usually at least contain the element name, symbol, and number could also include state at room temperature, atomic mass, and other details about the element o place elements in the same location Example: oxygen is always at group 16, period 2 1

3 Elements are arranged in groups (vertical columns) and periods (horizontal rows) o periods arranged in order of increasing mass o groups organized based on similar physical and chemical properties Example: nonreactive Noble Gases in group 18 TASK: Label the groups and periods on the following image. 2

4 Read p. 26 Metals and Non-metals The staircase line on the right side of the table separates the metals (left) and non-metals (right) Properties: Table 2.1 p. 26 Metals bright metallic shine (luster) easily shaped (malleable) solid at room temperature (except mercury) good conductor of heat and electricity Non-metals dull, various colors (not shiny) brittle solid or gas at room temperature (except bromine) poor conductor of heat and electricity Metalloids are elements that are between the metals and non-metals o have properties and characteristics of both metals and non-metals the human body contains all types of elements (metal, non-metal, and metalloid) o Exampe: iron used to release energy to cells carbon is key for sugars, carbohydrates, and proteins potassium helps maintain fluid balance in tissues Read Did You Know and Off the Wall p. 27 TASK: Highlight the staircase on the previous page image as well as identify the metals, non-metals, and metalloids with different colors. Discuss CYU p. 30 #1-4 3

5 Reading the Periodic Table Investigation 2-A p. 28 The periodic table contains important information about the elements. To give you practice using it, use the periodic table at the back of your textbook to find the information needed to complete the chart below. Element Name Symbol Period Group chromium Analysis P Metal or Non-metal State of Matter bohruim 7 synthetic tin Cl Nb 5 15 metal 14 non-metal 1. Which part of the table was easiest to complete: the ones with the element name, the symbol, the period number or the group number? 2. Look at the elements that you classified as metals. On which side of the staircase line are they located? 3. Some lines on the table only give you the group number and the period number. How did you use this information to find the element name and symbol? 4. What patterns did you notice while looking at the element numbers in the periodic table? 4

6 Metal or Non-metal? BLM 2-2 Can you tell whether a substance is a metal or non-metal by looking at its properties? Identify the substances shown here. Consider their characteristics, then place a checkmark in each column that applies. Is the substance a solid, liquid, or gas? Put your answer in the second-last column. Decide whether the substance is metal or non-metal. Place your conclusion in the last column. Substance Shiny (lustrous) Easily Shaped (malleable) Conducts Heat and Electricity Can be Pulled into a Wire (ductile) State S = solid L = liquid G = gas Metal or Non-metal? gold bar s metal neon sign tin can silver coins magnesium fire starter copper pipe phosphorous glow stick oxygen 5

7 2.2 Elements and Compounds pp Read pp Elements cannot be broken down into simpler substances they are the simplest substance known Compound substance made up of two or more different elements that are chemically combined See Classification of Matter Flowchart (Figure 2.9 p. 31) compounds can be broken apart into simpler substances through the process of a decomposition reaction o Example: Oxygen, O, is a pure substance, consisting of one element Distilled water is a pure substance made of more than one element H 2 O (l) = 2-H + 1-O Hydrogen and Oxygen are chemically combined and form a compound o Electrolysis of Water (decomposition rxn) water is a pure substance molecule compound that can be broken into elements use electricity to cut water molecules decompose into elements 2H 2 O (l) 2H 2(g) + O 2(g) Test for compounds released hydrogen pop test (explosion) flame test for oxygen (glowing splint reignites) Everything is made from elements Most substances in the world are compounds Read Career Connect p. 33 Discuss CYU p. 34 #1-4 6

8 Uses of Elements and Compounds BLM 2-3 Everything in the universe contains elements. Most things are compounds that are a combination of elements. Use the knowledge you have gained in this unit to: decide whether items are elements or compounds; and match the common name of a substance to its scientific name and formula. 1. Complete the chart below. The first row has been done for you. Substance Element or Compound? Uses aluminum, Al (s) element baseball bats, foil, manufacturing carbon, C (s) carbon dioxide, CO 2(g) copper, Cu (s) glucose, C 6 H 12 O 6(s) gold, Au (s) helium, (He (g) ) limestone (calcium carbonate), CaCO 3(s) methane, CH 4(g) propane, C 3 H 8(g) silver, Ag (s) sucrose, C 12 H 22 O 11(s) tungsten, W (s) 2. Many products have familiar names as well as the official IUPAC name scientists use. Match the consumer products in column A with the appropriate IUPAC name and formula in column B by writing the correct letter from B in the blank beside the correct term in A. The table on page 37 of the science.connect 1 textbook will help you. A i. baking soda ii. used to bleach hair iii. battery acid iv. food seasoning v. table salt vi. road de-icer vii. cleaner B (a) sulfuric acid (H 2 SO 4(l) ) (b) sodium phosphate (Na 3 PO 4(s) ) (c) sodium bicarbonate (NaHCO 3(s) ) (d) magnesium chloride (MgCl 2(s) ) (e) monosodium glutamate (NaC 5 H 8 NO 4(s) ) (f) hydrogen peroxide (H 2 O 2(l) ) (g) sodium chloride (NaCl (s) ) 7

9 2.3 Chemical Names and Formulas pp Read p. 35 In 1919 a group of chemists from around the world came together to form the International Union of Pure and Applied Chemistry (IUPAC) o They set an international standard for chemical symbols and names so they would be consistent around the world o Today all countries use these symbols All element symbols use one or two letters, often the first letter of the name is used o i.e. carbon = C Once all letters were used, they used the first letter of the element name and a second letter from the name o i.e. calcium = Ca Some elements were discovered when the Latin form of the word was used, and given symbols based on their historic names o i.e. lead (plumbum) = Pb Read p. 36 Chemical formulas are used to represent compounds elements form. formulas are made up of letters and numbers. o letters indicate which element is in a substance, o subscript numbers indicate the proportion on the element in the substance o subscript letter tells you the state of matter Example: i.e. (s)=solid (l)=liquid (g)=gas C 6 H 12 O 6 (s) = 6 Carbon atoms 12 hydrogen atoms 6 oxygen atoms in a solid state 8

10 Discuss CYU p. 37 #1-3 9

11 Chemical Formulas Name each of the following chemical compounds (make sure you use the right naming scheme!) and determine how many atoms of each element are present: Chemical Compound Name Number of Atoms for Each Element Present 1. CaF 2 calcium fluoride 1 calcium, 2 fluorine 2. Be(OH) 2 3. NO 2 4. Al 2 (SO 4 ) 3 5. NH 4 NO 3 6. S 2 F 2 7. Na 2 CO 3 8. CH 4 9. LiNO S 2 F Na 3 PO Si(OH) CaBr PbBr CaSO CuCO H 2 O 18. NaCl 10

12 Interpreting Chemical Formulas BLM 2-6 Find out Activity p. 37 Complete the activity using the following table. Compound Name Common Use Chemical Formula Number and Name of Elements Total Number of Atoms calcium carbonate chalkboard chalk CaCO 3(s) sodium phosphate heavy duty cleaner Na 3 PO 4(s) magnesium chloride de-icing roads MgCl 2(s) monosodium glutamate (MSG) food seasoning NaC 5 H 8 NO 4(s) hydrogen peroxide bleach and disinfectant H 2 O 2(l) glucose sugar C 6 H 12 O 6(s) carbon dioxide freon-12 fizz in pop, dry ice refrigerator coolant CO 2(g) CCl 2 F 2(g) 1. (a) What information do the subscript numbers in a chemical formula provide? For example, what does the 2 mean in Cl 2? (b) If there is no subscript number, what number is understood? 2. Strychnine is an extremely poisonous compound with the chemical formula C 21 H 22 N 2 O 2(l). (a) How many elements are present in strychnine? (b) What is the total number of atoms represented by this formula? Show your work. 11

13 Pure Substances Crossword BLM 2-7 Chapter 2 Vocabulary Check Complete the crossword using the clues provided. Across 1. one of the most important tools for chemists (2 words) 6. the smallest form of an element 8. These elements tend to be malleable and shiny. 10. A pure substance that contains two or more elements. 12. played cards with the elements to develop a periodic table 13. elements found on the right side of the periodic table 15. There is one atom of this element in every particle of water (H 2 O). 16. This title describes a person who tried to make gold from lead. 18. an element short form that is the same in every language (2 words) 20. shorthand that describes a chemical (2 words) 21. vertical columns of the periodic table Down 1. rows in the periodic table 2. association that standardized element symbols and chemical names 3. process that can separate elements from compounds (2 words) 4. simplest form of a pure substance 5. He discovered phosphorous. 7. process used to plate metal onto a substance 9. This element is found in pop cans and baseball bats. 11. This gas makes balloons float. 14. This property describes shine. 17. This poisonous metal is a liquid at room temperature. 19. an element that gives plumbers their title 12

14 Chapter 2 Review Questions 1) Describe how the modern periodic table is organized. (2.1) 2) What does the staircase line in the periodic table separate? (2.1) 3) List the common properties of metals and non-metals. (2.1) 4) Name four parts of the periodic table. (2.1) 5) What information is found in each cell of the periodic table? (2.1) 6) Explain the relationship between a particle and an atom. (2.1) 7) What can a decomposition reaction tell you about a substance? (2.2) 13

15 8) Explain the difference between an element and a compound. (2.2) 9) Describe two clues that would tell you whether a substance is an element or a compound. (2.2) 10) What is the symbol for bohrium in German, French, and Chinese? (2.3) 11) List six chemicals you may find in your home or at school. (2.3) 12) Name and write the formula for five common compounds. (2.3) 13) What do the letters and numbers in a chemical formula tell you? (2.3) 14

16 Complete Chapter 2 Review Questions p. 38 #1-14 Please record your answers below or on an attached sheet of loose leaf. 15