Answer:
Water splitting is the chemical reaction in which water is broken down into oxygen and hydrogen: 2 H2O → 2 H2 + O. Efficient and economical photochemical water splitting would be a technological breakthrough that could underpin a hydrogen economy.
Explanation: 2 H2O → 2 H2 + O.
Assuming the molar mass of oxygen is 18.01, you only need 16 grams (B) of oxygen because the molar mass of hydrogen is about 1 gram.
16+1+1=18
