The $H^{+}$ ion is a ...... .

Consider the following reaction involving two acids shown below: formic acid and $HF$.
$K^+F^- + HCOOH \rightleftharpoons HCOO^-K^+ + HF$
Given: $pK_a$ of $HCOOH = 3.8$ and $pK_a$ of $HF = 3.2$.
Which of the following statements about this reaction are true?
$(A)$ Formic acid is the strongest Bronsted acid in the reaction
$(B)$ $HF$ is the strongest Bronsted acid in the reaction
$(C)$ $KF$ is the strongest Bronsted base in the reaction
$(D)$ $KO_2CH$ is the strongest Bronsted base in the reaction
$(E)$ The equilibrium favours the reactants
$(F)$ The equilibrium favours the products
$(G)$ Formic acid has a weaker conjugate base
$(H)$ $HF$ has a weaker conjugate base

Which of the following acids would have a $STRONGER \ CONJUGATE \ BASE$?
$(A)$ $H_2S$ $(1)$ vs $H_2O$ $(2)$
$(B)$ Glutarimide $(3)$ vs Piperidin$-2-$one $(4)$
$(C)$ $CH_3C \equiv CH$ $(5)$ vs $CH_3CH = CH_2$ $(6)$

Classify the following species into Lewis acids and Lewis bases and show how these act as such:
$(a) HO^{-}$
$(b) F^{-}$
$(c) H^{+}$
$(d) BCl_{3}$

Arrange $NH_4^+$,$H_2O$,$H_3O^+$,$HF$,and $OH^-$ in increasing order of their acidic strength.

The ammonium ion $(NH_4^+)$ is: