Question

How many grams of oxygen would be produced by the electrolysis of 72.0 grams of water ? 2H2O--> O2+2H2 (Must be made to fit into the chart underneath #8)

Answer 1

Molar mass H₂O = 18.0 g/mol   and O₂ = 32.0 g/mol

2 H₂O --------> O₂ + H₂

(2* 18.0 g ) H₂O ---------->  32 g O₂
72.0 g H₂O ----------------> ?

mass of O₂ = 72.0 * 32 / 36

mass of O₂ = 2304 / 36

= 64 g of O₂

hope this helps!