GHS Honors Chemistry

Stoichiometry Problems Worksheet 1

Name: ______Date: ______Block: ______

CHEMISTRY

1. Given the unbalanced decomposition reaction of baking soda:

NaHCO3 (s) + heat ===> Na2CO3 (s) + CO2 (g) + HOH (g)

How many grams of each product are produced by the decomposition of 42.0 grams of baking soda?

2. The catalytic decomposition of hydrogen peroxide is:

H2O2 (aq) ===> H2O (l) + O2 (g)

Balance the reaction. How many moles of water and oxygen are produced by the decomposition of 68.0 grams of hydrogen peroxide? How many molecules of water and oxygen are produced? How many grams of each product are formed?

3. If 156.0 grams of potassium metal reacts with excess water, then how many grams of potassium hydroxide and hydrogen gas are formed? Be sure to balance the reaction first.

K(s) + H2O(l)  KOH(aq) + H2(g)

4. Determine the number of moles of carbon dioxide gas, water, and sodium chloride formed by the reaction of 42.0 grams of sodium bicarbonate (baking soda) reacting with excess hydrochloric acid. The reaction is:

NaHCO3 (s) + HCl(aq) ===> CO2 (g) + HOH (l) + NaCl(aq)

GHS Honors Chemistry

Stoichiometry Problems Worksheet 1

Name: ______Date: ______Block: ______

5. The unbalanced decomposition reaction of butane gas in excess oxygen produces carbon dioxide gas and water vapor: C4H10 (l) + O2 (g) ===> CO2 (g) + H2O (l). Starting with 11.6 grams of butane, how many grams of carbon dioxide gas and water vapor are formed?

6. The burning of solid sulfur in air produces sulfur dioxide gas.

S + O2  SO2

Balance the reaction. How many moles and molecules of sulfur dioxidedoes the burning of 3 moles of sulfur form?

7. The Haber reaction produces ammonia, an important nitrogenous compound needed to make plant fertilizers. The unbalanced reaction is: N2 (g) + H2 (g) ===> NH3 (g) + heat. Is the reaction exothermic or endothermic ? If 170.0 grams of ammonia are produced, then how many grams of nitrogen gas and hydrogen gas are needed? How many molecules of each reactant are needed?

9. Given the reaction: H2 (g) + O2 (g) ===> HOH (g). How many moles of hydrogen gas and oxygen gas are needed to produce 1.25 moles of water vapor ? How many molecules of each reactant are needed?

  1. The unbalanced synthesis reaction between aluminum metal and oxygen is:

Al (s) + O2 (g) ===> Al2O3 (s).

If 6.02 X 10 25 molecules of aluminum oxide are produced, then how many grams of aluminum metal and oxygen gas are needed?

11. The decomposition of mercury (II) oxide to produce liquid mercury and gaseous oxygen is shown in this unbalanced reaction:

HgO(s) + heat ===> Hg (l) + O2 (g)

How many grams of mercury (II) oxide are needed to produce 100.3 grams of liquid mercury ?

12. The unbalanced synthesis reaction of hydrogen gas with chlorine gas produces hydrogen chloride gas:

H2 (g) + Cl2 (g) ===> HCl(g)

How many molecules of hydrogen gas are needed to produce 146.4 grams of hydrogen chloride gas?