Answer : The correct option is, (2) \(HC_2H_3O_2\text{ and }H_3PO_4\)
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 \((H^+)\) and a bases is a type of substance that ionizes in the water to give hydroxide ion \((OH^-)\).
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, \(CH_3COOH\) can easily gives the hydrogen ion but \(CH_3CH_2OH\) can not gives the hydrogen ion due to stronger O-H bonding. So, these formulas does not represent Arrhenius acids.
In option 2, \(CH_3COOH\) and \(H_3PO_4\) can easily gives the hydrogen ion. So, these formulas represent Arrhenius acids.
In option 3, \(KHCO_3\) and \(KHSO_4\)can not gives the hydrogen ion because both are the salts. So, these formulas does not represent Arrhenius acids.
In option 4, \(NaSCN\) and \(Na_2S_2O_3\)can not gives the hydrogen ion because no hydrogen present in the compound. So, these formulas does not represent Arrhenius acids.
Hence, (2) \(HC_2H_3O_2\text{ and }H_3PO_4\) represent Arrhenius acids.
