NEETChemistryChemical Kinetics
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): For a zero-order reaction, the time required for 100% completion is exactly twice its half-life. Reason (R): The rate of a zero-order reaction continuously decreases as the concentration of the reactant decreases. In the light of the above statements, choose the most appropriate answer from the opt
Options
- ABoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A)
- BBoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A)
- CAssertion (A) is true but Reason (R) is false
- DAssertion (A) is false but Reason (R) is true
Correct answer
C. Assertion (A) is true but Reason (R) is false
Step-by-step solution
Assertion (A) is true. For a zero-order reaction, the time required for 100% completion is t_ 100 % = [ A ]₀ k , while the half-life is t_ 1/2 = [ A ]₀ 2k . Thus, t_ 100 % = 2 t_ 1/2 . Reason (R) is false. By definition, a zero-order reaction has a constant rate that is independent of the concentration of the reactant. The rate does not decrease as the reactant is consumed. Answer: Assertion (A) is true but Reason (R) is false