Answer to Question #129100 in General Chemistry for MIKE WHITE

Question

How many kilograms of oxygen are required to form 2.86kg of CU2O?

Answer 1

4Cu + O₂ → 2Cu₂O

M(O₂) = 32 g/mol

M(Cu₂O) = 143 g/mol

n=m/M

n(Cu₂O) = 2860 g / (143 g/mol) = 20 mol

Proportion:

1 mol – 2 mol

x mol – 20 mol

x = 10 mol (O₂)

m=n×M

m(O₂) = 10 mol × 32 g/mol = 320 g

Answer: 0.32 kg