Equations & Stoichiometry Review

1. How many oxygen atoms are in 3Ba(ClO3)2?

a. 3 b. 2

c. 9 d. 18

2. Which of the following is NOT an indication that a chemical reaction has taken place?

a. Formation of gas b. color change

c. Production of water d. production of a precipitate

3. A balanced equation will have

a. the same subscripts

b. equal number of each type of atom in both the reactants and products

c. the same coefficients

d. the reactants and products will be the same

4. AgNO3(aq) + NaCl(aq) à AgCl(s) + NaNO3(aq) is an example of what type of reaction?

a. Synthesis b. decomposition

c. Single-replacement d. double-replacements

5. According to the activity series, will the following reaction occur?

Mg (s) + 2H2O (l) à Mg(OH)2 (aq) + H2 (g)

a. Yes, because Mg is higher than H2 on the table

b. Yes, because Mg is lower than H2 on the table

c. No because Mg is lower than H2 on the table

d. No because Mg will only react with water hot enough to be steam

6. Which types of reactions are known as displacement reactions?

a. single-replacement b. synthesis

c. double replacement d. both a and c

7. How is a reaction written that includes the use of a catalyst?

a. the name or formula of the catalyst written above the arrow

b. the name or formula of the catalyst written within the arrow

c. the name or formula of the catalyst is added to the end of the reaction

d. An arrow pointing up is used to show that a catalyst has been used

8. The following reaction shows which type of chemical reaction

Ca (s) + H2O (l) à Ca(OH)2 (s) + H2 (g)

a. synthesis b. decomposition

c. single replacement d. double replacement

9. Which of the following chemical equations match the following reaction?

Sodium Carbonate yield Sodium Oxide and Carbon Dioxide

a. NaCO3 à NaO + CO2

b. Na3CO3 à Na2O + CO2

c. Na2CO3 à Na2O + CO2

d. Na2CO3 à Na3O + CO2

10. Which of the following equations shows a decomposition reaction?

a. Silver Oxide and Sodium Hydroxide yield Silver Hydroxide and Sodium Oxide

b. Methane and Oxide yield Carbon Dioxide and Water

c. Sodium Carbonate yields Sodium Oxide and Carbon Dioxide

d. Hydrogen and Iodine yield Hydrogen Iodide

11. Combustion Reactions always

a. yield carbon dioxide and hydrogen

b. yield carbon dioxide and water

c. have carbon dioxide and water as reactants

d. have oxygen as a product

12. Which of the following reactions is balanced correctly

a. 2Ag2O à 4Ag + O2

b. 4Ag2O à 8Ag + 2O2

c. 2Fe + 3O2 à 2Fe2O3

d. 2Al + 2NiSO4 à 3Ni + Al2(SO4)3

13. According to the Activity Series, which element will replace Lead but not Nickel?

a. Hydrogen

b. Cobalt

c. Tin

d. Cadmium

14. The maximum amount of product that can be produced from a given amount of reactant is

a. actual yield

b. theoretical yield

c. percent yield

d. limiting reagent

15. The limiting reagent is defined as

a. The substance that is not used up completely in a reaction

b. The reactants in a chemical reaction

c. The reactant that limits the amount of product that can form

d. The product that is limited

16. The number of moles of each reactant and product in a chemical equation is represented by

a. The subscripts

b. The coefficients

c. The number of products

d. Cannot be determined by the equation

17. Which of the following calculates percent yield

a. (actual yield/theoretical yield)

b. (theoretical yield/ actual yield)

c. (theoretical yield/ actual yield) * 100

d. (actual yield/ theoretical yield) * 100

18. A substance that changes the rate of a chemical reaction without being consumed is known as a (n)

a. catalyst

b. reactant

c. product

d. reagent

19. Which type of reaction is represented by the following?

A + BX à AX + B

a. synthesis

b. decomposition

c. single replacement

d. double replacement

20. According to the activity series, will the following reaction occur?

Cu (s) + HCl (aq) à CuCl (aq) + H2 (g)

a. Yes because Cu is below H2 on the activity series list

b. Yes because Cu is above H2 on the activity series list

c. No because Cu does not react with water

d. No because Cu does not react with acid

Short Answer

21. What are the 4 indicators that a chemical reaction has occurred?

22. Change the following word equation into a chemical equation, balance the equation and tell what type of reaction it is:

Solid Magnesium and Copper (II) Nitrate in aqueous solution yield Magnesium Nitrate in aqueous solution and solid Copper

23. Determine if the following reaction will occur and write a balanced equation

Chlorine gas and Potassium Iodide in aqueous solution

24. Write a balance equation, determine phases, the write an ionic equation and a net ionic equation for the reaction between Cu2SO4 and Fe

25. Write a balance equation, determine phases, the write an ionic equation and a net ionic equation for the reaction between Mg and FeCl3

SHOW ALL WORK

26. Find the mass of all of the products given the following information

Fe2O3 + CO à Fe + CO2

40 g of Fe2O3

27. Determine the limiting reagent of the following

Cu + AgNO3 à Cu(NO3)2 + Ag

2.5 mol of Cu and 5.5 mol of AgNO3

28. Calculate percent yield of the following

CO +2H2 à CH3OH

If 75 g of CO reacts to produce 68.4 g CH3OH, what is the percent yield of CH3OH?

29. Calculate the percent yield for the following

C2H6 + O2 -> CO2 + H2O

45 g C2H6 makes 42 L CO2

Determine if the reactions happen, then write the balanced chemical reaction. If a reaction could happen, then make the reaction happens! You might need to determine requirements to make it happen!! The give phases, write the ionic equation and the net ionic equation.

30. Magnesium and water.

31. Calcium and water.

32. Calcium and phosphoric acid.

33. Tin and copper (I) chloride.

34. Copper and Sulfuric Acid.

Answer Key

1. d

2. b

3. b

4. d

5. d

6. d

7. a

8. c

9. c

10. c

11. b

12. a

13. c

14. b

15. c

16. b

17. d

18. a

19. c

20. d

21. Gas production, Formation of a precipitate, Color Change, Hear/Energy Formation

22. Mg(s) + Cu(NO3)2 (aq) à Mg(NO3)2 (aq) + Cu(s)

23. A reaction will occur and the balanced equation is

Cl2 (g) + 2KI (aq)à 2KCl (aq) + I2 (s)

24. Balanced Equation: Cu2SO4 + Fe à Fe SO4 + 2Cu

Ionic Equation: Fe(s) + 2Cu1+(aq) + SO42-(aq)) à 2Cu(s) + Fe2+(aq) + SO42-(aq

Net Ionic Equation: Fe(s) + 2Cu1+(aq) à 2Cu(s) + Fe2+(aq)

25. Balanced Equation: 3Mg + 2FeCl3à 3MgCl2 + 2 Fe

3Mg + 2Fe+3 + 6Cl-1 à 3Mg+2 + 6Cl-1 + 2Fe

3Mg + 2Fe+3 à 3Mg+2 + 2Fe

26. Balanced equation: Fe2O3 + 3CO à2Fe + 3CO2

40 g Fe2O3 (1 mol Fe2O3 / 159.70 Fe2O3 g )(2 mol Fe/1 mol Fe2O3 )(55.85 g Fe/1 mol Fe) = 27.98 g Fe

40 g Fe2O3 (1 mol Fe2O3 / 159.70 Fe2O3 g )(3 mol CO2 /1 mol Fe2O3 )(44.01 g CO2 /1 mol CO2) = 33.07 g CO2

27. Cu + 2AgNO3 à Cu(NO3)2 + 2Ag

2.5 mol Cu (2 mol Ag/1 mol Cu) = 5 mol Ag

5.5 mol AgNO3 (2 mol Ag/2 mol AgNO3) = 5.5 mol Ag

Copper is the limiting reagent

28. CO +2H2 à CH3OH

If 75 g of CO reacts to produce 68.4 g CH3OH

75 g CO (1 mol CO/28.01 g CO)(1 mol CH3OH /1 mol CO)( 32.05 g CH3OH /1 mol CH3OH) = 85.82 g CH3OH

68.4 g CH3OH/85.82 g CH3OH = 79.7 % yield

29. 2C2H6 + 7O2 -> 4CO2 + 6H2O

45 g C2H6 makes 42 L CO2

45 g C2H6 (1 mol C2H6 / 30.08 g C2H6)(4 mol CO2/2 mol C2H6)(22.4 L CO2/1 mol CO2) = 67.02 L CO2

42 L CO2 / 67.02 L CO2 = 62.67% yield

30. Magnesium and water react

Mg + H2O -> No Reaction (water must be steam)

31. Calcium and water react

Ca(s) + 2H2O(l)-> Ca(OH)2(aq) + H2(g)

Ca + 2H2O -> Ca+2 + 2OH- + H2

Net ionic the same as ionic equation

32. Calcium and phosphoric acid react

3Ca(s) + 2H3PO4(aq) -> Ca3(PO4)2(s) + 3H2(g)

3Ca + 6H+ + 2PO4-3 -> Ca3(PO4)2 + 3H2

Net ionic the same as ionic equation

33. Tin and copper (I) chloride react

Sn(s) + 2CuCl(aq) -> SnCl2(aq) + 2Cu(s)

Sn + 2Cu+ + 2Cl- -> Sn+2 + 2Cl- + 2Cu

Sn + 2Cu+ -> Sn+2 + 2Cu

34. Copper and Sulfuric Acid.

No Reaction – Copper does not react with acids