Which of the following is the strongest acid?

An aqueous solution of an acid is characterized by the presence of:

The dissociation of $H_3PO_4$ takes place in how many steps?

Values of dissociation constant,$K_a$ are given as follows:

Acid	$K_a$
$HCN$	$6.2 \times 10^{-10}$
$HF$	$7.2 \times 10^{-4}$
$HNO_2$	$4.0 \times 10^{-4}$

Correct order of increasing base strength of the bases $CN^{-}$,$F^{-}$ and $NO_2^-$ will be:

Write the conjugate base of the following: $HF, CH_{3}NH_{3}^{+}, H_{3}PO_{4}, HPO_{4}^{2-}$

Weak acids are partially ionised in aqueous solutions. The ionisation constants of some acids are given below. Arrange these acids in increasing order of their acid strength.

Acid Index	Acid Name and Ionisation Constant $(K_a)$
$1$	Formic acid $(HCOOH)$: $1.8 \times 10^{-4}$
$2$	Hypochlorous acid $(HClO)$: $3.0 \times 10^{-8}$
$3$	Nitrous acid $(HNO_2)$: $4.5 \times 10^{-4}$
$4$	Hydrocyanic acid $(HCN)$: $4.9 \times 10^{-10}$