2 H2 + O2 → 2 H2O
1) How many moles of H2O are produced when 5 moles of oxygen are used?

We'll produce 10 moles of H2O if 5 moles of O2 are used

Explanation:

Step 1: Data given

Number of moles oxygen = 5.0 moles

Step 2: The balanced equation

2H2 + O2 → 2H2O

Step 3: Calculate number of moles of H2O produced

For 2 moles H2 we need 1 mol O2 to produce 2 moles H2O

For 5.0 moles O2 we'll need 2*5 = 10 moles H2 to produce 2*5 = 10 moles H2O

We'll produce 10 moles of H2O if 5 moles of O2 are used

10 moles

Explanation:

The equation for the reaction is given below:

2H2 + O2 → 2H2O

From the equation above,

1 mole of O2 produced 2 moles of H2O.

Therefore, 5 moles of O2 will produce = 5 x 2 = 10 moles of H2O

Therefore, 10 moles of H2O are produced when 5 moles of O2 is used up.