PbSO₄ partially dissociates in water. the balanced equation is;
PbSO₄(s) ⇄ Pb²⁺(aq) + SO₄²⁻(aq)
Initial - -
Change -X +X +X
Equilibrium X X
Ksp = [Pb²⁺(aq)] [SO₄²⁻(aq)]
1.6 x 10⁻⁸ = X * X
1.6 x 10⁻⁸ = X²
X = 1.3 x 10⁻⁴ M
Hence the Pb²⁺ concentration in underground water is 1.3 x 10⁻⁴ M.
[Pb²⁺] = 1.3 x 10⁻⁴ M.
= 1.3 x 10⁻⁴ mol / L x 207 g / mol
= 26.91 ppm
You multiply the number by 1000 when you convert a measurement from kilometres to metres.
The prefix <em>kilo</em> means <em>×1000</em>, so
1 <em>kilo</em>metre means 1 metre <em>×1000</em>.
Atomic mass / mass number / atomic weight
(all of which mean the same thing)
A circuit breaker must be replaced after too much current flowing through it causing it to melt.
