Answer
Balanced equation:
$1 AgI(s) \lt -- \gt 1 Ag^{+}(aq) + 1 I^{-}(aq)$
$K_{sp}$ expression:
$K_{sp} = [Ag^{+}] \times [I^{-}]$
Work Step by Step
1. Identify the ions in the compound:
$Ag^{+}$ and $I^{-}$
2. Write the dissociation equation, where the solid ionic compound produces its ions in the water:
$ AgI(s) \lt -- \gt Ag^{+}(aq) + I^{-}(aq)$
Balance the equation:
$1 AgI(s) \lt -- \gt 1 Ag^{+}(aq) + 1 I^{-}(aq)$
3. To get the $K_{sp}$ expression, multiply the ions concentrations, where their balancing coefficients are the exponents of the molarities.
$K_{sp} = [Ag^{+}]^1 \times [I^{-}]^1$
$K_{sp} = [Ag^{+}] \times [I^{-}]$
