Question

How would you write the ionization equation for benzoic acid (${C_6}{H_5}COOH$)?

Answer 1

Hint: The benzoic acid is a weak acid which on dissolving in water partially dissociates to give its constituent ions. The ionization equation is given as the fraction of the original acid which has been ionized on dissolving in water.

Complete step by step answer:
The ionization is explained as the process where the atom or the molecules acquires a negative charge and positive charge by gaining or losing the electrons.
The benzoic acid (${C_6}{H_5}COOH$), is soluble in water which on dissolving dissociates to give its constituent ions.
The benzoic acid is a weak acid which dissolves in water and partially dissociates to give its constituent ions.
${C_6}{H_5}COOH + {H_2}O \to {H_3}{O^ + } + {C_6}{H_5}CO{O^ - }$
In this reaction, benzoic acid reacts with water to form hydronium ion and benzoate ion.
An acid ionization constant is defined as the equilibrium constant for the ionization of the acid. The acid ionization constant is given by ${K_a}$.
The general ionization reaction of weak acid is shown below.
$HA(aq) \to {H^ + }(aq) + {A^ - }(aq)$
The acid ionization constant for the above reaction is given as shown below.
${K_a} = \dfrac{{[{H^ + }][{A^ - }]}}{{[HA]}}$
Where the products are written in the numerator and reactant is written in the denominator.
The acid ionization presents the fraction of the original acid which has been ionized on dissolving in water.
The acid ionization constant for the ionization of benzoic acid is shown below.
$\Rightarrow {K_a} = \dfrac{{[{H_3}{O^ + }][{C_6}{H_5}CO{O^ - }]}}{{[{C_6}{H_5}COOH]}}$

Note:
The value of ${K_a}$ helps to know the strength of the acid. Weak acids which have a higher value of ${K_a}$ are stronger than the acids with lower value of ${K_a}$. For stronger acids, the value of ${K_a}$ reaches infinity.