A gaseous compound 'A' decomposes simultaneously into gaseous products 'B', 'C' and 'D' with the rat — Chemical Kinetics Chemistry Question
Question
A gaseous compound 'A' decomposes simultaneously into gaseous products 'B', 'C' and 'D' with the rate constants 2 × 10^-3 s^-1, 3 × 10^-3 s^-1 and 1.93 × 10^-3 s^-1, respectively. If only A(g) was present initially at a pressure of 13.86 atm and the reaction is performed at constant volume and temperature, the partial pressure (in atm) of B(g) in the reaction mixture after 100 s from the start of reaction is
💡 Solution & Explanation
Total rate constant k_total = (2 + 3 + 1.93) × 10^-3 = 6.93 × 10^-3 s^-1. After 100 s, kt = 0.693, which is exactly one half-life. The pressure of A that reacted is 13.86 / 2 = 6.93 atm. The partial pressure of B formed is (k1 / k_total) × (Reacted A) = (2 / 6.93) × 6.93 = 2 atm. Therefore, correct answer is 2.