Question

In which of the following species is the oxidation number of sulfur less than 6?

A. SO3

B. Na2SO4

C. SO2

Answer 1

A.

O: $-2 \times 3 = -6$

S: +6

B.

Na: $+1 \times 2 = +2$

O: $-2 \times 4 = -8$

S: +6

C.

O: $-2 \times 2 = -4$

S: +4

Answer: option C. SO2