The $pK_a$ of a weak acid is $5.85$. The concentrations of the acid and its conjugate base are equal at a $pH$ of (in $.85$)

What is the $pH$ of a $2 \times 10^{-3} \ M$ solution of a monoacidic weak base if it ionizes to the extent of $5 \%$?

What will be the $pH$ of a $0.1 \ M$ $NH_3$ solution?

At $T$ $(K)$,if the ionisation constant of ammonia in solution is $2.5 \times 10^{-5}$,the $pH$ of $0.01 \ M$ ammonia solution and the ionisation constant of its conjugate acid respectively at that temperature are $(\log 2 = 0.30)$

If the degree of dissociation is $1.30\%$,what is the $K_a$ for $0.1 \ M \ CH_3COOH$?

In its $0.2 \, M$ solution,an acid ionises to an extent of $60 \%$. Its hydrogen ion concentration is.....$M$