Which among the following is a correct conjugate acid-base pair for the equation stated below?
$HCl + NH_3 \rightleftharpoons NH_4^{+} + Cl^{-}$

Phosphoric acid ionizes in three steps with their ionization constant values $K_{a_1}, K_{a_2}$ and $K_{a_3}$ respectively,while $K$ is the overall ionization constant. Which of the following statements are true?
$A.$ $\log K = \log K_{a_1} + \log K_{a_2} + \log K_{a_3}$
$B.$ $H_3PO_4$ is a stronger acid than $H_2PO_4^{-}$ and $HPO_4^{2-}$
$C.$ $K_{a_1} > K_{a_2} > K_{a_3}$
$D.$ $K_{a_1} = \frac{K_{a_3} + K_{a_2}}{2}$
Choose the correct answer from the options given below

In the equilibrium $HClO_4 + H_2O \rightleftharpoons H_3O^{+} + ClO_4^-$,which of the following statements is correct?

Which of the following compounds has the highest value of dissociation constant $(K_a)$?

If $pK_b$ of a base is $5$,then $K_a$ of its conjugate acid will be

When $HClO_4$ is dissolved in the weak acid $HF$,the following equilibrium is established:
$HF + HClO_4 \rightleftharpoons H_2F^+ + ClO_4^-$
Which of the following is the correct set of conjugate acid-base pairs?