Determine the mass of hydrogen gas if 36 grams of water undergoes electrolysis to produce hydrogen and oxygen.

2.01 g H₂

Explanation:

The chemical equation for the electrolysis of water is

2 H₂O  ⇒  2 H₂  +  O₂

Convert grams of water to moles.  The molar mass of water is 18.016 g/mol.

(36 g)/(18.016 g/mol) = 1.998 mol H₂O

Convert moles of water to moles of hydrogen by using the mole ratio.  By looking at the chemical equation, you can see that for every 2 moles of water consumed, 2 moles of hydrogen is produced.

(1.998 mol H₂O) × (2 mol H₂/2 mol H₂O) = 1.998 mol H₂

Now that you have moles of hydrogen, you can convert to grams.  The molar mass of hydrogen is 1.008 g/mol.

(1.998 mol) × (1.008 g/mol) = 2.01 g H₂

You will produce 2.01 grams of hydrogen

the reaction mixture contains some ammonia, plus a lot of unreacted nitrogen and hydrogen. the mixture is cooled and compressed, causing the ammonia gas to condense into a liquid. the liquefied ammonia is separated and removed. the unreacted nitrogen and hydrogen are then recycled back into the reactor .