Unit 5

Question 1

A balanced chemical equation allows one to determine the

Answer 1

mole ratio of any two substances in the reaction

Question 2

The coefficients in a chemical equation represents the

Answer 2

relative number of moles of reactants and products

Question 3

how many mole ratios can be correctly obtained from the chemical equation 2NO -> N2 + O2

Answer 3

3

Question 4

In the reaction Ca + Cl -> CaCl2, what is the mole ratio of chlorine to calcium chloride

Answer 4

1:1

Question 5

In the reaction N2 + 3H2 -> 2NH3, what is the mole ratio of nitrogen to ammonia

Answer 5

1:2

Question 6

What is the mole ratio of oxygen to phosphorus(V) oxide in the reaction P4(s) + 5O2(g) -> P4O10(s)

Answer 6

5:1

Question 7

In the chemical equation wA + xB -> yC + zD, if one knows the mass of A and the molar masses of A, B, C, and D, one can determine

Answer 7

the mass of any of the reactants or products

Question 8

If one knows the mass and molar mass of reactant A and the molar mass of product D in a chemical reaction, one can determine the mass of product D produced by using

Answer 8

mole ratio of D to A from the chemical equation

Question 9

What is needed to calculate the mass of ammonia gas produced from 2.o L of nitrogen gas in excess hydrogen gas in the reaction below? N2(g) + 3H2(g) –> 2NH3(g)

Answer 9

two molar masses, one density, and one mole ratio

Question 10

A chemical reaction involving substances A and B stops when B is completely used. Bis the

Answer 10

limiting reactant

Question 11

The substance that restricts the participation of other reactants in a chemical reaction is known as the

Answer 11

limiting reactant

Question 12

The substance not completely used up in a chemical reaction is known as the

Answer 12

excess reactant

Question 13

To determine the limiting reactant in a chemical reaction, one must know the

Answer 13

available amount of each reactant

Question 14

What is the ratio of the actual yield to the theoretical yield, multiplied by 100%

Answer 14

percent yield

Question 15

What is the measured amount of a product obtained from a chemical reaction

Answer 15

actual yield

Question 16

Actual yield must be determined by

Answer 16

theoretical yield

Question 17

The actual yield of a chemical reaction is

Answer 17

less than the theoretical yield

Question 18

In the chemical equation wA+xB –> yC+zD, how many correct mole ratios can be obtained that relate only the products

Answer 18

2

Question 19

In the chemical equation wA+xB –> yC+zD, a comparison of the number of moles of A to the number of moles of C would be a

Answer 19

mole ratio

Question 20

To determine the limiting reactant in a chemical reaction involving known masses of the two reactants, A and B, which of the following calculations would be the most useful

Answer 20

calculating the mass of a single product formed from each reactant