Question

What is acid and bases according to the Arrhenius concept ?

Answer 1

We know that acids are substances which are capable of donating a proton, whereas bases are substances which are capable of accepting a proton. A substance is an acid when its pH value is less than $7$ and is base when its pH value is greater than $7$.

Complete answer:
An aqueous solution is a solution in which the solvent is water. Whereas a non-aqueous solution is a solution in which water is not the solvent.
According to Arrhenius,
An acid is a substance that gives ${H^ + }$ ions on dissolving in the aqueous solution. It increases the concentration of ${H^ + }$ ions in the aqueous solution. Examples are Hydrochloric acid ($HCl$), Sulphuric acid (${H_2}S{O_4}$), Nitric acid ($HN{O_3}$), Acetic acid ($C{H_3}COOH$), etc. When $HCl$is dissolved in water it undergoes dissociation reaction to produce ${H^ + }$ ion and $C{l^ - }$ ion, it increases the concentration of the ${H^ + }$ ions in the obtained solution.
Whereas the base is a substance that gives $O{H^ - }$ ion on dissolving in the aqueous solution. It increases the concentration of $O{H^ - }$ ions in the aqueous solution. Examples are Sodium hydroxide ($NaOH$), Calcium hydroxide ($Ca{\left( {OH} \right)_2}$), magnesium hydroxide ($Mg{\left( {OH} \right)_2}$), etc. When, $NaOH$ dissolved in water, it gives $N{a^ + }$ ion and hydroxide ($O{H^ - }$) ion, it increases the concentration of $O{H^ - }$ ions in the obtained solution.
Note:
Since water is a neutral substance, which does not conduct electricity. Electrolytic dissociation (Arrhenius theory) is the process of dissolving some substance in water to conduct electricity. These substances are called electrolytes.