In the system, `LaCI_(3(s)) + H_(2)O(g)` + heat `rarr` LaCIO(s) + 2HCI(g) , equililbrium is established. More water vapour is added to restablish the equilibrium. The pressure of water vapour is doubled. The factor by which pressure of HCI is changed is

Options

A. 2
B. `sqrt(2)`
C. `sqrt(3)`
D. `sqrt(5)`

Answer

B

Explanation

`LaCI_(3)(s) + H_(2)O(g) + "heat" hArrLaCIO(s) + 2HCI(g)`
At eq. `P_(1) P_(2)`
`K_(p) = (P_(2)^(2))/(P_(1))`
When `P_(H_(2)O) = 2P_(1)` , Let `P_(HCI) = P'_(2)`
Then `K_(p) = (P'_(2)^(2))/(2P_(1))` `(P'_(2)^(2))/(1P_(1))` = `(P_(2)^(2))/(P_(1))`
`P'_(2)^(2) = 2P_(2)^(2)`
`P'_(2) = sqrt(2) P_(2)`
therefore pressure of HCI is change by `sqrt(2)` factor.