Question

If 30 ml of H2 and 20 ml of O2 react to form water. What is left at the end of the reaction.

Answer 1

2H2 + O2 ———> 2H2O

From above reaction equation
For 20 mL of O2 40 mL of H2 is required.
Therefore, limiting reagent is H2

So, Volume of H2O formed = 30 mL

Oxygen utilised = 15 mL
Left over oxygen = 20 mL - 15 mL = 5 mL

At end of reaction 30 mL water is formed and 5 mL of oxygen is left.

Answer 2

This is the answer..

Hope it helps..