On dissolving $1 \ mole$ of each of the following acids in $1 \ L$ of water,the acid which does not give a solution of strength $1 \ N$ is:

Identify the conjugate base of ${H_2}PO_3^-$ and the conjugate acid of ${HCO_3^-}$.

Observe the following species: $AlCl_3, NH_3, H^{+}, Co^{3+}, OH^{-}, Mg^{2+}, BF_3, Cl^{-}$. How many Lewis acids are present in the above list?

Identify the conjugate acid-base pair from the following equilibrium reaction.
$HSO_{3(aq)}^{-} + H_3O_{(aq)}^{+} \rightleftharpoons H_2SO_3 + H_2O$

Which one of the following substances has the highest proton affinity?

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