Question

How many grams of oxygen are produced from the electrolysis of 850g of water?

Answer 1

 2 H₂O(l) → 2 H₂(g) + O₂(g) 

Molar masses

$H_2O=18$

$O_2=32$

Moles of $H_2O=\frac{850}{18}=47.22moles$

Moles of $O_2=\frac{47.22}{2}=22.61moles$

Mass of $O_2=22.61×32=755.52grams$