Answer :

Answer:

A) MgCO₃ is insoluble

Explanation:

Based on the rules of solubility:

All nitrates are soluble. That means Pb(NO₃)₂ is soluble.

All ammonium ions are soluble. NH₄Br is soluble.

All phosphate are insoluble except when combined with group I ions (Li, Na, K...) K₃PO₄ is soluble.

Also, all carbonates are insoluble except when combined with group I ions. That means Li₂CO₃ is soluble and:

A) MgCO₃ is insoluble