The strongest base from the following species is

Which one of the following is not a base?

In the reaction where $HNO_3$ acts as a base,which of the following acts as the strongest acid?

Identify each species in the following equilibrium according to the code: $SA = \text{stronger acid}$; $SB = \text{stronger base}$; $WA = \text{weaker acid}$; $WB = \text{weaker base}$. The $pK_a$ of $(CH_3)_2NH_2^+$ is $10.7$ (conjugate acid of $(CH_3)_2NH$) and the $pK_a$ of $CH_3OH$ is $15.2$.
$CH_3OH$ $(1)$ + $(CH_3)_2NH$ $(2)$ $\rightleftarrows CH_3O^- + (CH_3)_2NH_2^+$

Which of the following is a Lewis acid?

The dissociation constants $(K_a)$ of four acids are given below. Which of these is the strongest acid?