[laddoo12]

the ksp of hypothetical A3B2 is 1.08E-23
calculate the solubility in 0.10 M A(NO3)2 [THE ANSWER About 5 x 10-11]

what i did was
AG(no3)2=A+2NO3  A=.1 M

ksp=[3A]^3[2B]^2 where A=s+.1 so i assumed A=.1
1.08E-23=[3(.1)]^3[2B]^2
then solving i get s to be 1E-11 for s :S i don't get why I'm off please help

[Borek]

ksp=[3A]^3[2B]^2

Why 3A?