Chromium plating can involve the electrolysis of an electrolyte of an acidified mixuture of chromic acid and chromium sulphate . If during electrolysis the article being plated increases in mass by 2.6 g and 0.6 dm3 of oxygen are evolved at an inert anode, the oxidation state of chromium ions being discharged must be:
(assuming `Cr=52) and I mole of gas at room temperature and pressure occupies a volume of 24 dm^3)

Options

A. `-1`
B. Zero
C. `+1`
D. `+2`

Answer

D