Thionyl chloride on reaction with white phosphorus gives a compound of phosphorus ' $C$ ' which on hydrolysis gives an oxo acid ' $O$ '. The correct statement about $C$ and $O$ are

I. Shape of ' $C$ ' is pyramidal

II. ' $O$ ' is a dibasic acid

III. ' $O$ ' is a monobasic acid

IV. ' $C$ ' on reaction with acetic acid given ' $O$ '

Which one of the following statements is not correct?

Consider the following.

Assertion (A) Phosphorus can form both phosphorus (III) and phosphorus (V) chlorides but nitrogen cannot form nitrogen (V) chloride.

Reason (R) The electronegativity of nitrogen is more than that of phosphorus.

The correct answer is

The correct statements about the compounds of boron are

I. In borax bead test, the colour of cobalt metaborate is blue.

II. Diborane is prepared by the oxidation of sodium borohydride with iodine.

III. In diborane oxidation state of hydrogen is +1 .

IV. Boric acid is a tribasic acid.