A sample of NH4HSs is placed in a 258 L flask containing 012

A sample of NH4HS(s) is placed in a 2.58 L flask containing 0.120 mol NH3(g).
NH4HS(s)NH3(g)+H2S(g ) KP=0.108 at 25

What will be the total gas pressure when equilibrium is established at 25C?

Express your answer using four significant figures.

Solution

              NH4HS(s) ---> NH3(g)     +         H2S(g)

Initial        sample     0.12*0.0821*298/2.58      0

                           = 1.14 atm

                         
change           -x            +x                    +x

Kp = pNH3*pH2S

0.108 = (1.14+x)*x

x = 0.088

total pressure at equilibrium,

pTotal = pNH3 + pHCl

        = 1.14+x + x

        = 1.14+0.088+0.088

        = 1.316 atm