Chapter 8

In the reaction 2H2 + O2 > 2H2O, what is the movie ratio of oxygen to water? a. 1:2 b. 2:1 c. 8:1 d. 1:4

a. 1:2

If a company was performing a chemical reaction, they would choose the chemical that is _____ as the excess reactant. a. least expensive and most abundant b. most expensive and least abundant c. least expensive and least abundant d. most expensive and most abundant

a. least expensive and most abundant

The actual yield of a chemical reaction is (usually) a. less then the theoretical yield b. greater than the theoretical c. equal to the percentage yield d. greater than the percentage yield

a. less then the theoretical yield

The substance that restricts the participation of other reactants in a chemical reaction is known as the a. limiting reactant b. limiting product c. excess reactant d. excess product

a. limiting reactant

A balanced chemical equation allows one to determine the: a. mole ratio of any two substances in the reaction b. energy released in the reaction c. electron configuration of all elements in the reaction d. mechanism involved in the reaction

a. mole ratio of any two substances in the reaction

In the reaction N2 + 3H2 > 2NH3, what is the most ratio of nitrogen to ammonia? a. 1:1 b. 1:2 c. 1:3 d. 2:3

b. 1:2

Percent yield represents the _____ of a chemical reaction. a. speed b. efficiency c. individual steps d. rate

b. efficiency

A chemical reaction involving substances A and B stops when B is completely used. B is the: a. excess reactant b. limiting reactant c. primary reactant d. primary product

b. limiting reactant

What is the ratio of the actual yield to the theoretical yield, multiplied by 100%? a. mole ratio b. percentage yield c. molar yield d. excess yield

b. percentage yield

the coefficients in a chemical equation represent the a. masses, in grams, of all reactants and products b. relative numbers of moles of reactants and products c. number of atoms in each compound in a reaction d. number of valence electrons involved in the reaction

b. relative numbers of moles of reactants and products

What is the mole ratio of oxygen to phosphorus(V) oxide in the reaction P4 +5O > P4O? a. 1:1 b. 1:5 c. 5:1 d. 4:10

c. 5:1

The substance not completely used up in a chemical reaction is known as the a. limiting reactant b. limiting product c. excess reactant d. excess product

c. excess reactant

The substance not completely used up in a chemical reaction is known as the: a. limiting reactant b. limiting product c. excess reactant d. excess product

c. excess reactant

The conversion factor which is found in all stoichiometry problems is: a. molar mass b. density c. mole ratio d. temperature

c. mole ratio

The study of the quantity relationships between the reactants and products in a chemical reaction is called: a. conversions b. reaction chemistry c. stoichiometry d. quantifying

c. stoichiometry

In the reaction Ca + Cl2 > CaCl2, what is the mole ratio of corn to calcium chloride? a. 2:3 b. 2:1 c: 1:2 d. 1:1

d. 1:1

For the reaction SO3 + H20 > H2SO4, calculate the percentage yield if 500.g of sulfur trioxide react with excess water to produce 575 g of sulfuric acid. a. 82.75% b. 88.3% c. 91.2% d. 93.9%

d. 93.9%

What is the measured amount of a product obtained from a chemical reaction? a. mole ratio b. percentage yield c. theoretical yield d. actual yield

d. actual yield

Actual yield must be determined by: a. estimations b. theoretical yield c. calculations d. experiments

d. experiments