To write the net ionic equation for the reaction between \(Na_2S \) and \(2HCl\), we first need to write the balanced molecular equation:

$$Na_2S (aq) + 2HCl (aq) → 2NaCl (aq) + H_2S (g) $$

Then, we identify the spectator ions, which are the ions that do not participate in the reaction. In this case, the spectator ions are \(Na^+ \) and \(Cl^- \).

The net ionic equation is:

$$S^{2-} + 2H^+ → H_2S (g) $$