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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

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

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प्रश्न

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

टीपा लिहा
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उत्तर

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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2021-2022 (March) Set 1

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