Question

20cc of 0.1m solution of metal ions is reacted with 20cc of 0.1 m sulphur dioxide solution.so2 reacted according to the equation so2+2H2O=(so4) -2 +H++2e-the original oxidation number of the metal was + 3 the new oxidation number of the metal would be

Answer 1

SInce the number of moles of the metal ions and SO2 is same, we can say that,(in terms of magnitude)

Change in O.N. of S=Change in O.N. of metal ion

It is given that SO2 oxidizes to (SO4)2- giving away 2 electrons.

Therefore, the metal ion must accept those 2 electrons.

Hence, the final O.N. of the ion will be=3-2=+1

Ans- +1