Question

Calculate the number of grams of methane required to react with 25 g of chlroine

Answer 1

From the balanced equation:
3mol CH4 react with 4 mol Cl2

Molar mass Cl2 = 71g/mol
25g Cl2 = 25/71 = 0.352 mol

This will react with 0.352/4*3 = 0.264 mol CH4
Molar mass CH4 = 16g/mol
0.264mol = 0.264*16 = 4.23 g CH4 required