when PbSO₄ is added it dissociates as follows
PbSO₄ --> Pb²⁺ + SO₄²⁻
molar solubility is the number of moles of solute that can be dissolved in 1 L of solution
if molar solubility of PbSO₄ is X, then molar solubility of Pb²⁺ is X and SO₄²⁻ is X
the formula for ksp is as follows
ksp - solubility product constant
ksp = [Pb²⁺][SO₄²⁻]
ksp = X * X
ksp = X²
ksp = 1.82 x 10⁻⁸
X² = 1.82 x 10⁻⁸
X = 1.35 x 10⁻⁴ M
molar solubility of PbSO₄ is 1.35 x 10⁻⁴ M
answer is b.
