Answer:
For 1: 3.3 moles of oxygen gas is required.
For 2: 14 moles of hydrogen gas is required.
For 3: 1.5 moles of oxygen gas is required.
Step-by-step explanation:
The chemical reaction of oxygen and hydrogen to form water follows:

- For 1: When 6.6 moles of
is reacted.
By Stoichiometry of the above reaction:
2 moles of hydrogen gas reacts with 1 mole of oxygen gas.
So, 6.6 moles of hydrogen gas will react with =
of oxygen gas.
Hence, 3.3 moles of oxygen gas is required.
- For 2: When 7.0 moles of
is reacted.
By Stoichiometry of the above reaction:
1 mole of oxygen gas reacts with 2 moles of hydrogen gas.
So, 7 moles of oxygen gas will react with =
of hydrogen gas.
Hence, 14 moles of hydrogen gas is required.
- For 3: When 3.0 moles of
is formed.
By Stoichiometry of the above reaction:
2 moles of water is formed from 1 mole of oxygen gas.
So, 3.0 moles of water will be formed from =
of oxygen gas.
Hence, 1.5 moles of oxygen gas is required.