Question

When silent electric discharge is passed through \( O _{2} \) gas, it converts into \( O _{3} \). If the density of final sample is 20 times the density of hydrogen gas under similar conditions, calculate the mass percent of \( O _{2} \) in the final sample.

Answer 1

Vd of O₂ = 16

Vd of O₃ = 16

Vd of Mixture = 20

Let no. of moles of O₂ : O₃ = n : 1

\(20 = \frac{16 \times n + 24 \times 1}{n + 1}\)

\(20n + 20 = 16n + 24\)

\(4n = 4\)

\(n = 1\)

\(\% \text{ of }O_2 = \frac{16 \times n}{16n +24} \times 100\)

\(= \frac{16 \times 1}{16\times 1 + 24} \times 100\)

\(= \frac{16}{40} \times 100\)

\(= 40\%\)