Question

What is the concentration (M) of sodium ions in 4.57 L of a 1.25 M Na3P solution?

Answer 1

Molarity/concentration is moles/ltr.

so,1.25 M $Na_3P$ means 1.25 moles of $Na_3P$ in one litre of solution.

$Na_3P \to 3Na^++P^-$

This implies,

1 mole of Na₃P means 3 mole of Na⁺

1.25 M Na₃​P means $3 \times 1.25 =3.75$ moles of Na⁺ per litre of solution.

Hence 3.75 moles of Na⁺ are present in per litre of solution.

Concentration of Na⁺ ions is 3.75 mol/L in the solution.