The states of the individual compounds is missing in the chemical equation.
The given compounds:
Na₂S + 2HCl → 2NaCl + H₂S
When metal sulfides such as the given sodium sulfide, react which acids, they form salt and hydrogen sulfide gas.
The complete chemical equation with the states of the compounds is written as;
[tex]Na_2 S_{(aq)} \ + \ 2HCl _{(aq)} \ \ --> \ \ 2NaCl_{(aq)} \ + \ H_2S_{(g)}[/tex]
where;
aq --- aqueous for liquid state
g --- gaseous state
Thus, we can conclude that, the states of the individual compounds is missing in the chemical equation.
Learn more about metal sulfides here: https://brainly.com/question/14204055
