In the thermal decomposition of `N_(2)O" at "764^(@)C`, the time required to decompose half the reactant was 263 seconds, when the initial pressure was 290 mm of Hg and 212 seconds at an initial pressure of 360 mm of Hg. What is the order of this reaction ?

Explanation

`(t_(1))/(t_(2))=((a_(2))/(a_(1)))^(n-1)`
`a_(1)="290 mm of Hg "t_(1)="263 seconds"`
`a_(2)="360 mm of Hg "t_(2)="212 seconds"`
`(263)/(212)=((360)/(290))^(n-1)`
`1.24=(1.24)^(n-1)`
`n-1=1`
`n=1+1=2`
Hence, the reaction is of second order.