`200 mL of 1M HCl = (1)/(1000) XX 200 = 0.2 M`
`NH_(3) ` and HCl react in equimolar Proporation to form `NH_(4)Cl`
`:. NH_(3)` evolved n the reaction = 0.2 M
`N_(2)(g) + 3H_(2) (g) hArr 2NH_(3)(g)`
No. of moles of `NH_(3)(g)` formed =0.2M
No. of moles of `N_(2)(g) " reacted " =(0.2)/(2) = 0.1M`
No. of moles of `H_(2)(g) " reacted " =0.2xx(3)/(2) =0.3M`
The molar concentration of various species at the equilibrium point is :
`{:(,N_(2)(g),+,3YH_(2)(g),hArr,2NH_(3)(g)),("Initial moles/litre",1,,3,,0),("Moles/litre at eqm. point",1-0.1,,3-0.3,,0.2),(,=0.9,,2.7,,):}`
Applying Law of chemical equilibrium :
`K_(c) = [[NH_(3)(g)]^(2))/[[N_(2)(g)][H_(2)(g)]^(3))= (0.2)^(2)/(0.9xx(2.7)^(3))=(0.04)/(17.71)=2..26xx 10^(-3)`