Suppose you had 2.0158 grams of hydrogen (H2).

How many moles of hydrogen do you have?

How many moles of oxygen would react with this much hydrogen?

What mass of oxygen would you need for this reaction?

How many grams of water would you produce?

A. How many moles of hydrogen do you have?

2.0158 g H2 (1 mol / 2.02 g) = 1.00 mol H2

B. How many moles of oxygen would react with this much hydrogen? The chemical reaction would be:

H2 + 1/2O2 = H2O

1.00 mol H2 (1/2 mol O2 / 1 mol H2) = 0.50 mol O2

C. What mass of oxygen would you need for this reaction?

0.50 mol O2 (32 g / 1 mol) = 16.00 g O2

D. How many grams of water would you produce?

1.00 mol H2 (1 mol H2O / 1 mol H2) (18.02 g H2O / 1 mol H2O) = 18.02 g H2O