8.7 moles of ammonia (NH3) is formed in the following reaction. How many grams of hydrogen reacted?

The formula for the formation of ammonia is 2 (N2) + 3 (H2) = 2 (NH3)

3 moles of H2 make 2 moles of NH3 so 8.7 * (3/2) = 13.05 moles of H2

A mole of H2 is 2.01588 grams. 2.01588 * 13.05 = 26.31 grams of hydrogen