Name _________________________________________________
H2(g) + O2 (g) = H2O(g)
The first step to any stoichiometry problem is to balance the equation!
Balance the above equation before solving the problems below.
1. What is the molar ratio of hydrogen gas to oxygen gas needed for the
synthesis of water?
2. If 10 moles of hydrogen gas are reacted with an excess of oxygen gas, how
many moles of water vapor will be produced?
3. If 10 moles of hydrogen gas are reacted with an excess of oxygen gas, how
many moles of oxygen gas were used in the reaction?
4. If 10 moles of oxygen gas react with an excess of hydrogen gas, how many
moles of water vapor will be produced?
5. If 6 moles of water vapor are produced, how many moles of hydrogen gas
were used in the reaction?
How many moles of oxygen gas were used?
6. If 4 balloons are filled with hydrogen gas, how many balloons of equal size
will need to be filled with oxygen gas to completely react with the hydrogen?
(Assume the temperature and pressure are the same for both gases.)
7. If the water vapor produced by the reaction in number 6 could be contained
in a balloon, how many balloons of water gas would be produced? (Assume
same temperature and pressure for all gases and assume balloon volumes
are equal.)
8. If 2 grams of hydrogen gas are reacted with an excess of oxygen gas, what
mass of water vapor will be produced?
What mass of oxygen gas was used in the reaction?
9. If 10 grams of water vapor are produced in the reaction, how many grams of
hydrogen gas were used in the reaction?
How many grams of oxygen gas were used in the reaction?
10. If 3 grams of oxygen gas were consumed in the reaction, how many grams of
hydrogen gas were used?
How many grams of water vapor were produced?
11. If 1 mol of hydrogen gas is used in the reaction, how many hydrogen
molecules are involved in the reaction?
How many hydrogen atoms are involved in the reaction?
12. If 2 mol of hydrogen gas are used in the reaction, how many O2 molecules
are used in the reaction?
How many oxygen atoms are involved?