Why can't sodium salts be produced through a reaction between a metal and an acid?
Normally, reacting a metal and an aqueous acid will produce a salt and hydrogen gas, as in the case of iron:

$$\ce{Fe (s) + 2HCl(aq) -&gt; FeCl2 (aq) + H2 (g)}$$

However, you should not use the same method to produce, for example, sodium chloride:

$$\ce{2Na (s) + 2HCl(aq) -&gt; 2NaCl (aq) + H2 (g)}$$

because sodium reacts violently with water.