Question

If a 0.24 g sample is burnt in air to produce 0.22 g of CO₂, what is the percent carbon in the sample?

(a) 92%

(b) 55%

(c) 25%

(d) 10%

Answer 1

Correct option is (c) 25%

C + O₂ → CO₂

Weight of carbon = \(\frac{12 \times 0.22}{44}\) = 0.06; 

% purity of carbon = \(\frac{0.06 \times 100}{0.24}\) = 25