According to the Arrhenius definition of acids: An Arrhenius acid is any species that increases the concentration of hydrogen ions in its aqueous solution.
Hydrogen Chloride gas ionises in water to give hydrogen and chlorine ions. Thus, it increases the concentration of hydrogen ions in the solution. So is hydrogen chloride gas considered to be an Arrhenius acid or is the aqueous solution of hydrogen chloride, i.e., HCl(aq.) gas an Arrhenius acid?
If the aqueous solution is an acid then why is hydrogen chloride gas referred to as an ‘acidic’ gas?
Similarly, is NaOH(s) an Arrhenius base or is NaOH(aq.) an Arrhenius base?