Question

At a certain temperature and a total pressure of `10^(5) Pa`, iodine vapour contains `40%` by volume of `I "atoms"`, Calculate `K_(p)` for the equilibrium.
`I_(2(g))hArr2I_((g))`

Answer 1

Correct Answer - `2.67 xx 10^(4)`
Partial pressure of I atoms,
`p_(t) = (40)/(100) xx p_("total")`
`= (40)/(100) xx 10^(5)`
`= 4 xx 10^(4) Pa`
`= 4 xx 10^(4) Pa`
Partial pressure of `I_(2)` molecules,
`p_(t_(2)) = (60)/(100) xx p_("total")`
`= (60)/(100) xx 10^(5)`
`= 6 xx 10^(4) Pa`
Now, for the given reaction,
`K_(p) = ((pl)^(2))/(p_(t))`
`= ((4 xx 10^(4))^(2) Pa^(2))/(6 xx 10^(4) Pa)`
`= 2.67 xx 10^(4) Pa`
`= 2.67 xx 10^(4) Pa`