When 10 mL of an aqueous solution of KMnO₄ was titrated in acidic medium, equal volume of 0.1 M of an aqueous solution of ferrous sulphate was required for complete discharge of colour. The strength of KMnO₄ in grams per litre is __________ $$\times$$ 10^$$-$$2. (Nearest integer)

[Atomic mass of K = 39, Mn = 55, O = 16]

In the sulphur estimation, 0.471 g of an organic compound gave 1.44 g of barium sulphate. The percentage of sulphur in the compound is ____________%. (Nearest integer)

(Atomic Mass of Ba = 137 u)

100 mL of Na₃PO₄ solution contains 3.45 g of sodium. The molarity of the solution is _____________ $$\times$$ 10^$$-$$2 mol L^$$-$$1. (Nearest integer)

[Atomic Masses - Na : 23.0 u, O : 16.0 u, P : 31.0 u]

A chloro compound "A".

(i) forms aldehydes on ozonolysis followed by the hydrolysis.

(ii) when vaporized completely 1.53 g of A, gives 448 mL of vapour at STP.

The number of carbon atoms in a molecule of compound A is ___________.