Question

One mole of `N_(2)O(g)` at `300K` is kept in a closed container under one atmosphere. It is heated to `600K` when `20%` by mass of `N_(2)O_(4)(g)` decomposes of `NO_(2)(g)`. The resultant pressure
A. `1.2 atm`
B. 2.4 atm
C. `2.0` atm
D. `1.0` atm

Answer 1

Correct Answer - B
`N_(2)O_(4)(g) hArr 2NO_(2)(g)`
At start `=100 // 92 mol = 1.08 mol ` 0
At equilibrium `80 // 92 mol = 0.86` `20 // 46 mol = 0.43 mol`
According to ideal gas equation, at two condition
At 300 K `P_(0)V=n_(0)RT_(0)`
`1 xx V = 1.08 xx R xx300` ....(i )
At 600K `P_(1)V = n_(2)RT_(1)`
`P_(1)xxV = (0.86+0.43) xx R xx 600` ....(ii)
Divide (ii) by (i)
`(P_(1))/(1) = (1.29xx600)/(1.08xx300), P_(1)= (1.29xx2)/(1.08) = 2.38 atm`.