Answer:
Q = 6.68x10⁻⁶
Step-by-step explanation:
The initial solutions are Pb(NO₃)₂ and NaBr. As sodium and nitrates salts are soluble, the insoluble product must be the formed from the other ions, PbBr₂.
The soluble product equilibrium is written as:
PbBr₂(s) ⇄ Pb²⁺(aq) + 2Br⁻(aq)
Where Q is defined as:
Q = [Pb²⁺] [Br⁻]²
As:
[Pb²⁺] = 0.0630M
[Br⁻] = 0.0103M
Q = [Pb²⁺] [Br⁻]²
Q = [0.0630M] [0.0103M]²
Q = 6.68x10⁻⁶