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In a first order reaction x → y, 40% of the given sample of compound remains unreacted in 45 minutes. Calculate rate constant of the reaction.

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Question

In a first order reaction x → y, 40% of the given sample of compound remains unreacted in 45 minutes. Calculate rate constant of the reaction.

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Solution

`k=2.303/tlog_10"[A]_@/[A]_t`

`k=2.303/tlog_10"100/40`

`k=2.303/45log_10"100/40`

`k=2.303/45log_10"2.5`

`k=2.303/45*0.3979`

`k=0.0204"min"^-1`

 

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2015-2016 (March)

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