Answer : The correct option is, (2) [tex]HC_2H_3O_2\text{ and }H_3PO_4[/tex]
Explanation :
Arrhenius theory : It sates that an acid is a type of substance that ionizes in the water to give the hydronium ion or hydrogen ion [tex](H^+)[/tex] and a bases is a type of substance that ionizes in the water to give hydroxide ion [tex](OH^-)[/tex].
Or we can say that,
Arrhenius acid are those which can easily gives the hydrogen ion in a solution and Arrhenius base are those which can easily gives the hydroxide ion in a solution.
In option 1, [tex]CH_3COOH[/tex] can easily gives the hydrogen ion but [tex]CH_3CH_2OH[/tex] can not gives the hydrogen ion due to stronger O-H bonding. So, these formulas does not represent Arrhenius acids.
In option 2, [tex]CH_3COOH[/tex] and [tex]H_3PO_4[/tex] can easily gives the hydrogen ion. So, these formulas represent Arrhenius acids.
In option 3, [tex]KHCO_3[/tex] and [tex]KHSO_4[/tex]can not gives the hydrogen ion because both are the salts. So, these formulas does not represent Arrhenius acids.
In option 4, [tex]NaSCN[/tex] and [tex]Na_2S_2O_3[/tex]can not gives the hydrogen ion because no hydrogen present in the compound. So, these formulas does not represent Arrhenius acids.
Hence, (2) [tex]HC_2H_3O_2\text{ and }H_3PO_4[/tex] represent Arrhenius acids.
