Use the ICE table approach as solution:
PbSO₄ --> Pb²⁺ + SO₄²⁻
I - 0 0
C - +s +s
E - s s
Ksp = [Pb²⁺][SO₄²⁻]
1.82×10⁻⁸ = s²
Solving for s,
s = <em>1.35×10⁻⁴ M</em>
Mass number = protons + neutrons = 34+46 =80
the element with an atomic number of 34 and mass number of 80 is selenium
