JEE Main levelSingle correct optionDifficulty 2 of 3qa209
AgCl dissolves in ammonia: AgCl+2NHX3[Ag(NHX3)X2]X++ClX−. Take Ksp(AgCl)=1.8×10−10 and Kf([Ag(NHX3)X2]X+)=1.6×107. The equilibrium [NHX3] needed to just dissolve 0.010 mol AgCl in 1 L is closest to
A0.09 M
B0.19 M
C3.47 M
D0.37 M
Answer: B
The overall constant is K=KspKf=2.88×10−3. With [[Ag(NHX3)X2]X+]=[ClX−]=0.010 M, K=(0.010)2/[NHX3]2 so [NHX3]=0.010/K=0.19 M.