Assign suitable reason for the following:
`H_3PO_3` is diprotic

(i) What happens when (a) Chlorine gas reacts with cold and dilute solution of NaOH? (b) XeF_(2) undergoes hydrolysis ? (ii) Assign suitable reasons for the following : (a) SF_6 is inert towards hydrolysis. (b) H_3PO_3 is diprotic. (c) Out of noble gases only Xenon is known to form established chemical compounds.

Assign suitable reason for the following: SF_6 in inert towards hydrolysis.

Assign reason for the following : (i) H_(3)PO_(2) is a stronger reducing agent than H_(3)PO_(4) . (ii) Sulphur shows more tendency for catenation than oxygen. (iii) Reducing character increases from HF to HI.

H_(3)PO_(3) is

Account for the following : (i) Ammonia is a stronger base than phosphine. (ii) H_(3)PO_(3) is a diprotic acid.