Question

Two H2 molecules can react with one O2 molecule to produce two H2O molecules. How many moles of hydrogen molecules are needed to react with one mole of oxygen molecules?

(a) 0.5 moles
(b) 1 mole
(c) 2 moles
(d) 4 moles

Answer 1

To react with one mole of oxygen, we need 0.5 moles of hydrogen molecules.

Step-by-step explanation:

The balanced chemical equation for the reaction is:

2 H₂ + O₂ → 2 H₂O

This equation tells us that two moles of hydrogen react with one mole of oxygen to produce two moles of water.

So, to react with one mole of oxygen, we need 0.5 moles of hydrogen molecules.

Therefore, the correct answer is (a) 0.5 moles.