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Obtain the expression for half-life and rate constant of the first-order reaction.

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Question

Obtain the expression for half-life and rate constant of the first-order reaction.

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Solution

k = `2.303/t log_10  [A]_0/[A]_t`

Where, `[([A]_0 = "Initial concentration"),([A]_t = "Final concentration")]`

At, t = `t_(1/2), [A]_t = [A]_0/2`

k = `2.303/t_(1/2)  log_10  [A]_t/([A]_0/2)`

k = `2.303/t_(1/2) xx log_10 2`

= `2.303/t_(1/2) xx 0.3010`

`t_(1/2) = 0.693/k`

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