Classify the following as acid (or) base using Arrhenius concept

${\mathrm{H}}_3{\mathrm{PO}}_4$

Classify the following as acid or base using Arrhenius concept: ${\mathrm{CH}}_3\mathrm{COOH}$.

Write a balanced equation for the dissociation of the following in water and identify the conjugate acid -base pairs.

${\mathrm{NH}}_4^{+}$

Write a balanced equation for the dissociation of the following in water and identify the conjugate acid -base pairs.

${\mathrm{H}}_2{\mathrm{SO}}_4$

Write a balanced equation for the dissociation of the following in water and identify the conjugate acid -base pairs.

${\mathrm{CH}}_3\mathrm{COOH}$.

Identify the Lewis acid and the Lewis base in the following reactions.

$\mathrm{CaO}+{\mathrm{CO}}_2\to {\mathrm{CaCO}}_3$

Identify the Lewis acid and the Lewis base in the following reactions.

${\mathrm{H}}_3{\mathrm{BO}}_3$ accepts hydroxide ion from water as shown below

${\mathrm{H}}_3{\mathrm{BO}}_3\left(\mathrm{aq}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\rightleftharpoons \mathrm{B}\left(\mathrm{OH}\right){}_4+{\mathrm{H}}^{+}$

Predict the nature of ${\mathrm{H}}_3{\mathrm{BO}}_3$ using Lewis concept