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Assertion: Half-life period of a reactio...

Assertion: Half-life period of a reaction of first order is independent of initial concentration.
Reason: Half-life period for a first order reaction `t_(1//2) = (2.303)/(K) log 2`.

A

If both assertion and reason are true and reason is the correct explanation of the assertion.

B

If both assertion and reason are true and reason Iis not the correct explanation of the assertion.

C

If assertion is true but reason is false.

D

If assertion is false but reason is true.

Text Solution

Verified by Experts

The correct Answer is:
A

For a first order reaction, `K = (2.303)/(t) "log"(a)/(a-x)`, where a is initial concentration, and x is the amount reatced in time `t`.
For hlaf-life `x = a//2, t = t_(1//2)`
`K = (2.303)/(K)"log"(a)/(a-a//2)`
`t_(1//2) = (2.303)/(K)log2 = (0.693)/(K)`.
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