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The decomposition of N2O5(g) at 320K according to the following equation follows first order reaction

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Question

The decomposition of N2O5(g) at 320K according to the following equation follows first order reaction:

`N_2O_(5(g))->2NO_(2(g))+1/2O_(2(g))`

The initial concentration of N2O5(g) is 1.24 x 10-2 mol. L-1 and after 60 minutes 0.20x10-2 molL-1. Calculate the rate constant of the reaction at 320K.

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Solution

Data: `N_2O_(5(g))->2NO_(2(g))+1/2O_2`

`[N_2O_5]_@=1.24xx10^-2molL^-1`

`[N_2O_5]_t=0.20xx10^-2molL^-1`

k=?   t=60min

Solution : 

`k=2.303/t log""([N_2O_5])/([N_2O_5])`

`k=2.303/60log""((1.24xx10^-2))/((0.2xx10^-2))`

k=0.0383x0.7924

k= 0.303min-1

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2013-2014 (March)

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