A definite amount of solid `NH_(4)HS` is placed in a flask aleady containing ammoina gas at a certain temperature and `0.50` atm pressure. `NH_(4)HS` decomposes to give `NH_(3)` and `H_(2)S` and at equilibrium total pressure in flask is `0.84` atm. The equilibrium constant for the reaction is:

Options

A. `0.30`
B. `0.18`
C. `0.17`
D. `0.11`

Explanation

`{:(,NH_(4)HS_((s)),hArr,NH_(3(g)),+,H_(2)S_((g))),("Before eqm.",,,0.5,,0),("After eqm.",,,0.5+P,,P):}`
`P_(T)=0.84=0.5+P+PimpliesP=0.17 atm`
`K_(p)=P'_(NH_(3))xxP'_(H_(2)S)`
`=(0.5+0.17)xx0.17=0.11 atm^(2)`