Question:

Which of the following statements regarding sulphur is incorrect?

The oxidation state of sulphur is never less than +4 in its compounds.

S2 molecule is paramagnetic.

At 600oC the gas mainly consists of S2 molecules.

The vapour at 200oC consists mostly of S8 rings.

Solution:

(a) S2 molecule is paramagnetic like O2 and both have two unpaired electrons. At elevated temperature (≈1000K) S2 is the dominant species and is paramagnetic like O2 (b) The vapour at 200oC consists mostly of S8 rings (c) S8(g) 600° → 3S2(g) (d). The oxidation state of sulphur ranges between -2 to +6 in different compounds e.g.