Question

Explain the following:

Sodium chloride dissolves in water but carbon tetrachloride is insoluble in water.

Answer 1

1. Sodium chloride (NaCl) is an ionic compound. Water is a polar solvent, so it attracts and separates the Na⁺ and Cl⁻ ions, causing NaCl to dissolve in water.
2. Carbon tetrachloride (CCl₄) is a non-polar covalent compound. It does not interact sufficiently with polar water molecules, so it is insoluble in water.

Thus, ionic/polar substances generally dissolve in polar solvents like water, whereas non-polar covalent substances do not.