How can you experimentally determine the pka of acetic acid?

Explanation:

The pKa value of acetic acid is determined experimentally by plotting pH titration curve.

The hydrogen ion, H+ concentration can be determined by performing a pH titration of a weak acid with a strong base like NaOH etc.

Starting from the dissociation equation for the acid,

HA(aq) + OH-(aq) --> H3O+(aq) + A−(aq)

we obtain for the point of half equivalence (where half of the acid has reacted with the base):

[A−] = [HA].

From the equilibrium equation

it therefore follows that

pKa = pH.

(a) (i) All the elements of a group have similar chemical properties because they have same no. of valence electrons in their outermost shell. (ii) All the elements of a period have different chemical properties because they have different no. of valence electrons in their atoms.