STANDARDChemistry-Chemical Kinetics
STANDARD Chemistry First Order Reactions MCQ Question
Type: MCQ-numerical-Medium-Class 12
A first order reaction has a rate constant 1.15 × 10⁻³ s⁻¹. How long will 5g of this reactant take reduce to 3g?
A
444 s
B
400 s
C
528 s
D
669 s
Correct Answer
Option A
Detailed Explanation
For a first order reaction, the time t can be calculated using the formula t = 2.303/k log(R₀/R), where R₀ is the initial amount and R is the remaining amount. Substituting R₀ = 5g, R = 3g, and k = 1.15 × 10⁻³ s⁻¹, t = 444 s.
Found an issue with this question?