Science 20F. Unit: Chemistry in Action. Student Notes. Name:

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1 Science 20F Unit: Chemistry in Action Student Notes Name:

2 Unit Checklist HERE ARE THE ITEMS YOU NEED TO KNOW FOR THE CHEMISTRY UNIT IN GR.10 UNDERSTAND HOW TO READ THE PERIODIC TABLE BASED ON THE ELEMENTS FAMILY, PERIOD AND VALENCY (Valence electrons) BE ABLE TO UNDERSTAND HOW ELEMENTS COMBINE BASED ON THE POSITION OF THE ELEMENT FROM THE PERIODIC TABLE. EX. ALKALI METALS WITH HALOGENS EXPLAIN USING THE PERIODIC TABLE HOW AND WHY ELEMENTS COMBINE IN SPECIFIC RATIOS. WRITE FORMULAS AND NAMES OF BINARY IONIC COMPOUNDS FOR BOTH COVALENT AND IONIC MOLECULES AND COMPOUNDS WRITE FORMULAS FOR COVALENT MOLECULES USING PREFIXES INVESTIGATE THE LAW OF CONSERVATION OF MASS AND RECOGNIZE THAT MASS IS CONSERVED (DID NOT CHANGE) IN A CHEMICAL REACTION BALANCE CHEMICAL EQUATIONS BE ABLE TO CLASSIFY THE TYPES OF CHEMICAL REACTIONS BE ABLE TO EXPLAIN ACIDS AND BASES PROPERTIES INVOLVING ph, REACTIVITY, AND INDICATORS NEUTRALIZATION REACTIONS FROM AN ACID AND BASE REACTION TECHNOLOGIES INVOLVED IN REDUCING EMISSIONS OF POTENTIAL AIR POLLUTANTS

WHAT ARE ELEMENTS Elements are the different or flavours that atoms can have.

characteristic or properties When atoms are together, they form.

3 ATOMS REVIEW Everything is made. When we everything (cells, protein, tables, fuel, gasoline, breath of air, nails, hormones etc ), we get a of joined together. There are different of atoms that form the we have in our entire. WHAT ARE ELEMENTS Elements are the different or flavours that atoms can have. Think of as a piece Think of as the types of pieces Every element has their own unique characteristic or properties When atoms are together, they form. That something can be made up of joined together or a of kinds joined together 1 Kind of Lego pieces or 1 kind of Element joined together forming a pure substance Different kinds of Lego pieces joined together, or different kinds of elements combined with each other forming compounds or molecules.

They are the broken down type of matter.

4 EXAMPLES OF ELEMENTS Oxygen, Carbon, Lead, Hydrogen, Lithium, Gold, Silver, Platinum, etc Everything on your ARE hence the Periodic Table of Elements! Elements be down any further. They are the broken down type of matter. If we were to down a bar of, you would have all atoms. ELEMENT OR NOT AN EL EMENT? Chlorine? Aluminum? Water? Carbon dioxide? Tin? Nitrogen? DNA? Cell?

5 This is the periodic table of elements All elements known to man are arranged in this chart. Elements are a substance that cannot be broken down further, so elements are atoms. Examples: Oxygen, Aluminum, Calcium are all elements STRUCTURE OF AN ATOM There are 3 particles: 1) 2) 3) : have a charge, are in the, and the number : have a charge, are on orbits around the nucleus, and equals the number (in pure atoms, not ions) : have charge, are in the nucleus, and equals the number minus the number

6 Electrons on outside Nucleus has Protons and Neutrons The is the big number in the top of each element box The is the small number the element s symbol ex: Protons = Electrons = 7 Neutrons = 7 N 14.01

7 HOW IS THE PERIODIC TABLE ARRANGED? There are on the periodic table. are the columns (up and down). are the rows (left and right). are the elements in the column. are the elements in the column. are the elements in the column. are the elements in the column. are the elements in the last ( column. Groups go up and down.

can only be a of valence electrons has valence electron, has 2 electrons, etc BOHR DIAGRAMS diagrams show

8 WHAT DO THESE COLUMNS TELL US? Tells you how many there are. Valence electrons Found on the most of an atom Only combine or into atoms to bonds In elements than metals, there can only be a of valence electrons has valence electron, has 2 electrons, etc BOHR DIAGRAMS diagrams show electrons in shells 1 st shell has a of 2 nd and 3 rd shells have of 8 electrons The electron number on the shell are your DRAW BOHR DIAGRAM OF BORON AND SILICON electrons.

9 WHY ARE VALENCE ELEC TRONS IMPORTANT? An is happy when it has a shell of (like the noble gases) Elements will try to 1 or 1 valence electron on its valence shell. Ex. Sodium has, so it will try lose electrons to form bonds. Ex. Cl has electrons, so it will try to gain 1. Periodic table The periodic table is into two basic types of elements, and.

10 The are on the of the periodic table and the nonmetals are on the of the periodic table. The metals and non-metals are by the. All elements along the stair-case are known as that have of both metals and non-metals. Covalent Bonding These are bonds that occur two (or more). We will have to them and also write the from

11 Naming bonds use when naming The prefixes are (1), di (2), (3), tetra (4), (5), and (6), septa (7), octa (8), nona (9), deca (10) You name the normally adding a if there are or more of that element Then, you name the element ending in - using a no matter how many there are. ex: Name the following: a) CCl 4 b) N 2 O 5 Writing Formulae from Names When given a name, write the appropriate and number based on what the name says. ex: Write the formulae for: a) dihydrogen monoxide Try these

12 1. CO 2. N 2 O 3 3. SiF 4 4. diarsenic trisulfide 5. nitrogen tribromide 6. diphosphorous pentoxide 7. diboron hexahydride 8. N 2 S 3 9. Br 2 Ionic Bonding These are bonds between and. For now, we will focus on the between one and one. Again, we will both name and write for these types of bonds. One major difference from covalent bonds is that ionic bonds use prefixes! Naming Ionic Bonds To start, you name the first. Then, you name the second element ending in -. ** USE PREFIXES** ex: Name CaBr 2 Writing Formulae for Ionic Bonds An is any charged particle.

13 Basically any on the periodic table can be charged The column metals will have a of +1, the column +2, then +3, then +/- 4. After the column, we get negative ions. The fifth column is -3, then -2, then -1 and the gases have no charge (they can t be ions!) So, in order to write the formula for an bond, you have to first figure out the charges on each ion in the name. Then you the numbers (forget about the + and signs). **Make sure after you switch the numbers, you put them below the letters** This will allow you to have a neutral compound (all the positives need to balance out the negatives). ex: Write the formulae for: a) Calcium Fluoride b) Aluminum sulfide Ionic bonding with transition metals These bonds involve metals from the metals family ( of the periodic table) Some transition metals can carry than 1 charge, ex. Iron (Fe) can be Fe 2+ or Fe 3+ To show the charge, are used. Ex. Iron (II) Oxide Because of the (II), Iron has a 2+ charge

14 Therefore, Fe 2+ O 2- FeO Ex. Iron (III) oxide Fe 3+ O 2- Fe 2 O 3 So the do play a big part! Ex. Copper (II) Fluoride Going backwards Au 2 O 3 What kind of bond? Ionic bond Au is Gold F is Fluorine Gold is a transition metal so we need roman numerals. The roman numerals will be the number found on the opposite element. Gold(III) Oxide Complex Ionic Bonds

15 These involve the reaction between one and a ion of 2 or more non-metals Naming is the same as before but the part end in -ide but rather it s named using the ion chart. Writing works the same but you should always put a complex ion in before you criss-cross. ex: Name CaSO 4 ex 2: Name Al(CH 3 COO) 3 ex 3: What s the formula for sodium carbonate? ex 4: What s the formula for aluminum chromate? Chemical reaction

16 How do we write a chemical reaction? Say we react vinegar with baking soda. Vinegar is CH 3 COOH Baking soda is NaHCO 3 The reaction: 2 Carbon, 2 Oxygen, 4 Hydrogens CH 3 COOH + NaHCO 3 NaCH 3 COO + H 2 CO 3 Questions to consider When we reacted the vinegar with baking soda, what happened to the power? And the liquid? Did I lose the vinegar and the baking soda? Did they just vanish into thin air? After the reaction, was my mass the same as before? What do you think happened to them? Law of conservation of mass The of substances produced (products) by a chemical reaction is equal to the of the substances (reactants). What does this mean? The of the reactants is the as the mass of the Also The of atoms in the reactants has to the number of atoms in the

17 Types of Reactions There are 6 basic types of reactions that can occur when reactants are reacted with each other. These are: (neutralization) Types of Chemical reactions Complete the following Info on the various types of chemical reactions 1. Synthesis: General formula: Chemical reaction: Illustration of a synthesis reaction A short analogy or story of a synthesis reaction:

18 Balance the synthesis reaction only: CuO Cu + O 2 Mg + Cl 2 MgCl 2 PbCO 3 PbO + CO 2 2. Decomposition: General formula: Chemical reaction: Illustration of a decomposition reaction

19 A short analogy or story of a decomposition reaction: Balance the decomposition reaction only: CuO Cu + O 2 Mg + Cl 2 MgCl 2 PbCO 3 PbO + CO 2 NO + O2 NO2 Ag 2 CO 3 Ag 2 O + CO 2

20 3. Combustion: General formula: Chemical reaction: Illustration of a combustion reaction A short analogy or story of a combustion reaction: Balance the combustion reaction only: NaHCO 3 Na 2 CO 3 + CO 2 + H 2 O FeCl3 Fe + Cl

21 C 2 H 6 + O 2 H 2 O + CO 2 CH 3 OH + O 2 CO 2 + H 2 O Ag 2 CO 3 Ag 2 O + CO 2 What are the products of all combustion reaction? 4. Single Dispalcement: General formula: Chemical reaction: Illustration of a single displacement reaction A short analogy or story of a single displacement reaction:

22 Balance the single displacement reactions only: KOH + HNO 3 H 2 O + KNO 3 BaCl 2 + H 2 SO 4 BaSO 4 + HCl F 2 + 2KI I 2 + 2KF Li + H 2 O H 2 + LiOH Ag 2 CO 3 Ag 2 O + CO 2 5. Double displacement: General formula: Chemical reaction: Illustration of a double displacement reaction

23 A short analogy or story of a double displacement reaction: Balance the double displacement reactions only: KOH + HNO 3 H 2 O + KNO 3 BaCl 2 + H 2 SO 4 BaSO 4 + HCl F 2 + 2KI I 2 + 2KF Li + H 2 O H 2 + LiOH BaCl 2 + Na 2 SO 4 BaSO 4 + NaCl

24 Balancing chemical equations Example: Al + O 2 Al 2 O 3 How many of each do I have? How does that make sense? They are not equal! Let s make them equal: If I have 1 Al atom on the left, and 2 Al on the products side, let s make 2 Al on the reactants side to balance with the 2 on the right. Let s make them equal: If I have 1 Al atom on the left, and 2 Al on the products side, let s make 2 Al on the reactants side to balance with the 2 on the right. Now we have 2 oxygen on the left and 3 oxygen on the right we need to make them equal. How about we make them both equal to 6 Multiply Oxygen from reactants by 3 Multiply Oxygen from products by 2

25 Al + O 2 Al 2 O 3 Is it balanced now? Let s try it The numbers we multiplied are to be put IN FRONT of the elements/compounds 2Al + 3O 2 2Al 2 O 3 Can we balance the aluminum? YES WE CAN! Multiply the Aluminum by 4 Instead! 4Al + 3O 2 2Al 2 O 3 Examples 1. NaCl + BeF 2 --> NaF + BeCl 2 2. FeCl 3 + Be 3 (PO 4 ) 2 --> BeCl 2 + FePO 4 3. AgNO 3 + LiOH --> AgOH + LiNO 3 4. CH 4 + O 2 --> CO 2 + H 2 O 5. Mg + Mn 2 O 3 --> MgO + Mn

26 Acids and Bases Student Ver. Notes and work booklet Brainstorm with your neighbor or in a small group the following: True or False Quiz *Note: This activity is not for marks! Directions: After each statement, indicate whether you think it is True (T) or False (F). Be truthful and answer to the best of your knowledge. Good luck! 1. All acids will or dissolve many materials or substances. 2. All acids should be considered dangerous because they will burn your skin. 3. There is only one test for an acid: to see if it will dissolve something. 4. Strong acids react with metals faster than weak acids. 5. Acids are made using bases. 6. Acids typically taste sour, while bases typically taste bitter. 7. All chemicals with H atoms in their formula are acids, and all chemicals with OH in their formula are bases. 8. Acids are stronger than bases. 9. The strength of acids and bases can be recorded using the ph scale. 10. Acids have a lower ph than bases. 11. The concentration of an acid or a base tells you how strong that acid or base is.

27 Introduction: What is an ACID? An acid is a substance (compound) that contains an to it. Examples: HCl Hydrochloric acid HNO 3 Nitric acid HBr Bromic acid CH3COOH Acetic Acid Properties of acids Acid reacts with Have taste Acids neutralize What does that mean? Whenever an acid is placed into a (in water), the released. See the diagram below. The more H+ that is released, the the acid. What does releasing or dissociating a H + ion mean? It means that when the Acid is in water to form a, the H+ will be separated and found as an ion. The H+ is separated from the ion ( )See diagram below. The example below is an example of HCl in water. The H+ from the Cl-.

28 Here are some common examples of ACIDS notice the alone H+ that is attached to the acid. HCl hydrochloric acid o This is your acid o It has a ph of 1 HNO3 nitric acid o Used in making fertilizers o Can be used in o Can be used in wood working o Extremely corrosive as it reacts with protein (basically what you are made of!) H2SO4 Sulfuric acid o Drain cleaner o Found in car (carries electrons) o Other cleaning agents and fertilizers HF Hydro fluoric acid o Highly corrosive that can dissolve through metals and glass o Reactive with metals but not plastics o Can cause painless burns that will eat up the calcium inside your body causing cardiac arrest CH3COOH Acetic acid (Household vinegar) o Weak acid o Used in cooking o Not very reactive but will react with base (baking soda)

29 What is a BASE? Instead of having a H+ that can be given off as in an ACID, a BASE is one that gives off a Bases usually contain a OH- Just like an acid, a base releases a OH- Just like an acid, a base releases a OH- Properties of bases Neutralizes acids Feels and tastes (soap)

30 Here are some common examples of bases notice the alone OH- that is attached to the base. Sodium hydroxide (NaOH) or Is a solid until dissolve to make a solution Slippery when touched Found in most Very caustic (causes burns) Used in paper making industries, paint stripping, food preparation Potassium hydroxide (KOH) Calcium hydroxide Ca(OH)2 Found in to. NH3 Ammonia contains no OH but is still considered as a base Is a base Found in our urine Ammonia was thought to be a life compound that cannot be man-made as it was produced by living things until Joseph Presley (1774) isolated it and revolutionized chemistry as now it is believed that life compounds can be synthesized. The 6 th type of chemical reaction - Mixing acids and bases Mixing an acid and a base will give a reaction. o A neutralization reaction is a reaction. o Salt and water are the products of a neutralization reaction. Salt is NOT just NaCl!!!! Ex. HCl + NaOH (or just H 2 O) Salt Ex. HCl + KOH (or just H 2 O) Salt Measuring the acidity or base-ness of acids and bases

Since acids mainly contain H+ ion, a ph scale is developed A ph scale was developed to rate the in a

ph Scale ranges from 0 14 where is the middle point (where water is found).

Example of ph scale with various substances The the number on the ph scale, the more it is.

31 Since acids mainly contain H+ ion, a ph scale is developed A ph scale was developed to rate the in a solution ph stands for where each step is more powerful than the previous. ph Scale ranges from 0 14 where is the middle point (where water is found). Any ph reading that is greater than 7 is considered or alkaline and any reading below 7 is considered Example of ph scale with various substances The the number on the ph scale, the more it is. The the number on the ph scale, the more it is. How do we test the acidity of a substance? There are various such as,, Universal indicator and others. Phenolphthalein

32 Phenolphthalein is when PINK but turns colourless when it becomes an acid. P A C - Phenolphthalein is Acid when clear Contains phenolphthalei n Contains phenolphthalei n Contains phenolphthalein with base (NaOH) Litmus Papers Review: Pink Litmus Paper Blue Litmus Paper Turns Blue when Basic Notice the first letters of BLUE and BASIC Turns Red when Basic Or Blue for Basic 1. How is an acid defined as in terms of chemistry? What about Base? 2. List all the characteristics of an acid and of a base 3. What does it mean when a H+ or OH- ion is dissociated? 4. What are always the products of a neutralization reaction? 5. What type of reaction (single displacement, double displacement, synthesis, decomposition) is a neutralization reaction? 6. Complete the reactions

33 a. Ca(OH) 2 + HCl b. HF + NaOH c. HCl + NaOH d. Mg(OH) 2 + HBr e. HNO 3 + NaOH 7. Describe how to read a ph scale 8. Which of the following would have a higher ph? a. NaOH or HCl b. Vinegar or milk c. Drano or lemon juice d. Car battery or blood e. HF or Ca(OH) 2 9. You placed a drop of phenolphthalein indicator in an unknown solution. The solution turns pink, what can you conclude about the ph of the solution? 10. You dipped a red litmus paper in lemon juice. What colour should you expect the paper to turn? 11. You dipped a blue litmus paper in lemon juice. What colour should you expect the paper to turn? 12. You dipped a red litmus paper in Drano (with NaOH). What colour should you expect the paper to turn? 13. A solution with phenolphthalein and 50ml HCl has turned the solution colourless. What type of solution can you put in to change the colour back into pink? How much? Answer Keys: Review Key 1. Acid releases H+ while a base releases OH- in solution (with water) 2. Review the notes above

3. H+ is released into solution when it is dissolved in water for acids while OH- is released into solution when it is dissolved in water 4. Salt and water 5. Double displacement 6. a. CaCl2 + H2O b.

34 3. H+ is released into solution when it is dissolved in water for acids while OH- is released into solution when it is dissolved in water 4. Salt and water 5. Double displacement 6. a. CaCl2 + H2O b. NaF + H2O c. NaCl + H2O d. MgBr2 + H2O e. NaNO3 + H2O 7. Review the notes 8. High ph means it is more basic a. NaOH b. Milk c. Drano since it is NaOH d. Blood (ph of about 8.0) e. Ca(OH)2 9. It is basic 10. Stays the same 11. Turns red 12. Turns blue 13. A strong base such as NaOH and exceed 50ml since 50ml will just neutralize it completely, having over 50ml will make it basic.

UNIT 2 CHEMISTRY IN ACTION. Mr.Yeung

UNIT 2 CHEMISTRY IN ACTION. Mr.Yeung UNIT 2 CHEMISTRY IN ACTION Mr.Yeung ATOMS REVIEW Check out the Scale of the Universe http://htwins.net/scale2/ Keep the following questions in mind: 1. Are cells bigger or smaller than atoms? 2. Generally