Home › ISC Class 12 › Chemistry › Chemical Kinetics › In the first order gas phase reaction A(g) -> B(…
In the first order gas phase reaction A(g) -> B(g) + C(g) followed by total pressure, pi is the initial pressure of A and pt the total pressure at time t. What is the partial pressure pA of A at time t?
Apt - pi
B2pi - pt
Cpi + pt
Dpt - 2pi
Answer & Solution
Correct answer: B. 2pi - pt
1. If x is the decrease in A, then B and C each rise by x, so $p_t = (p_i - x) + x + x = p_i + x$.
2. Hence $x = p_t - p_i$.
3. $p_A = p_i - x = p_i - (p_t - p_i) = 2p_i - p_t$.
4. Distractor A gives x itself, not pA; distractor C adds pressures incorrectly.
_Source: NCERT Class 12 Chemistry Ch 3 "Chemical Kinetics", p.14_
Related questions
It is observed that for many reactions the rate constant nearly doubles for a rise in tempThe half-life for the radioactive decay of carbon-14 is 5730 years and decay is first ordeIn a pseudo first order reaction, [A]/mol L^-1 reads 0.31 at t = 30 s and 0.17 at t = 60 sIn collision theory, what is meant by the collision frequency (Z)?According to collision theory, in the modified rate expression Rate = P Z_AB e^(-Ea/RT), wHow does a catalyst increase the rate of a chemical reaction?The first order rate constant for decomposition of ethyl iodide is 1.60 x 10^-5 s^-1 at 60The rate constants of a reaction at 500 K and 700 K are 0.02 s^-1 and 0.07 s^-1 respective