Chapter 12 Review Sheet                                                 Name ___________________________________

 

True-False

Classify each of these statements as always true, AT; sometimes true, ST; never true, NT.

_____1. In a chemical reaction between two reactants, the limiting reagent will be the reactant               with the smaller mass.

_____2. Normally, the actual yield in a chemical reaction will be equal to or less than the                          theoretical yield.

_____3. The coefficients in a balanced chemical equation can be used to form mole ratios relating           reactants to products.

_____4. Representative particles and moles are conserved in chemical reactions.

_____5. The coefficients in a balanced chemical equation tell the relative volumes of interacting             gases, expressed in any suitable unit of volume.

_____6. The actual yield of a chemical reaction can be calculated using mole ratios.

_____7. In endothermic reactions, the energy content of the products is higher than the energy               content of the reactants.

_____8. The amount of product can be determined from the amount of excess reagent.

 

 

Problems:

9. How many moles of oxygen are required to burn 4.8 mol of butane (C4H10) completely?                   

                                     2C4H10(g) + 13O2(g) è 8CO2(g) + 10H2O(g)

 

 

 

All of the following questions apply to the following reaction.

Show your work, include the units and use the correct number of significant figures.

10. If 32.4 mole of CO react with excess Fe2O3 , how many moles of Fe will form?

 

 

 

11. If 10.3 g of Fe2O3 react with excess CO, how many moles of CO2 will form?

 

 

 

12. If 8.82 mol of Fe are formed, how many liters of CO2 will form at STP?

 

 

 

13. If 10.4 g of Fe are formed, how many g of Fe2O3 must have reacted?

 

 

 

14. If 16.4 L of CO2 are formed, how many liters of CO reacted at STP?

 

 

 

15. If 32.5 g of Fe are formed, how many liters of CO2 are also formed at STP?

 

 

 

16. If 25 mole of CO react with 85 mole Fe2O3

            A. what is the limiting reagent?

 

 

 

            B. How many moles of Fe are produced

 

 

 

            C. How much excess reagent remains.

 

 

 

17. If 148 g of CO react with 158 g Fe2O3

            A. what is the limiting reagent?

 

 

 

 

            B. How many moles of Fe can be produced

 

 

 

 

            C. How much excess reagent remains.

 

 

 

 

            D. When this reaction is carried out in the lab, 37 g of Fe are produced, what is the percent yield?

 

 

 

 

            E. If the percent yield is 85%, how many grams of Fe will be produced?