In which of the following order of reaction, the half-life is independent of initial concentration?
Correct answer: B. 1st order
- A. Zero order
- B. 1st order
- C. 2nd order
- D. 3rd order
Explanation
In a first-order reaction, the rate of the reaction is directly proportional to the concentration of the reactant. Mathematically, it's expressed as: Rate = k[A], where "k" is the rate constant and "[A]" is the concentration of the reactant. The integrated rate equation for a first-order reaction is ln([A]₀/[A]) = kt, where "[A]₀" is the initial concentration of the reactant. When solving for half-life, you get t1/2 = 0.693 / k, where "k" is the rate constant. As shown by this expression, the half-life of a first-order reaction is indeed independent of the initial concentration.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Reaction Kinetics
Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.
Practise Reaction Kinetics
573 free Reaction Kinetics MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Reaction Kinetics questions
Which of the following statements about order of reaction is incorrect?
Order of reaction is the number of reacting molecules whose concentration alters as a result of chemical change. For which order of reaction, the unit of rate constant (k) is the same as that of rate of reaction?
The minimum amount of energy required for an effective collision is called activation energy. Which one of the following statements is incorrect about activation energy?Ea =Activation energy K = Specific rate constant
All of the following factors affect rate of reaction EXCEPT:
The addition of catalyst to a reaction can.
The experimental relationship between rate of reaction and concentration of reactant is called: