Question

39. Which of the following substances are insoluble in water? Select all that apply.

Answer 1

A, B, and C are insoluble in water

Answer 2

Answer:

B) BaSO₄ and C) Mg₃(PO₄)₂

Explanation:

We can use the solubility rules to decide which substances are insoluble.

You have probably learned NAG SAG and "Cats Cradle Old People," Sally Said.

I've listed them below.

$\begin{array}{lll}\textbf{Soluble} & \textbf{Insoluble}\\\textbf{N}\text{itrates} &\textbf{C} \text{arbonates }\\ \textbf{A}\text{cetates} & \textbf{C}\text{hromates}\\ \textbf{G}\text{roup 1} & \textbf{O}\text{ hydrOxides}\\ & \textbf{P} \text{hosphates}\\\textbf{S}\text{ulfates} &\textbf{S} \text{ulfites}\\ \textbf{A}\text{mmonium}& \textbf{S}\text{ulfides}\\\textbf{G}\text{roup 17} & \\\end{array}$

These aids help you remember that:

The salts of Group 1 metals are soluble (Li₂CO₃ and KOH).

Sulfates are usually soluble, except for BaSO₄. Thus, BaSO₄ is insoluble.

Phosphates are insoluble — Mg₃(PO₄)₂

The two insoluble compounds are BaSO₄ and Mg₃(PO₄)₂.