Question

How many moles of O2 are required to react with 6.6 moles of H2?

How many moles of H2 are needed to react with 7.0 moles of O2?

How many moles of H2O form when 3.0 moles of O2 reacts?

Answer 1

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.

Explanation:

The chemical reaction of oxygen and hydrogen to form water follows:

$O_2+2H_2\rightarrow 2H_2O$

• For 1: When 6.6 moles of $H_2$ 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 = $\frac{1}{2}\times 6.6=3.3mol$ of oxygen gas.

Hence, 3.3 moles of oxygen gas is required.

• For 2: When 7.0 moles of $O_2$ 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 = $\frac{2}{1}\times 7=14mol$ of hydrogen gas.

Hence, 14 moles of hydrogen gas is required.

• For 3: When 3.0 moles of $H_2O$ 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 = $\frac{1}{2}\times 3.0=1.5mol$ of oxygen gas.

Hence, 1.5 moles of oxygen gas is required.