The catalyst used in the production of elemental sulphur from H2S (by oxidation-reduction) is _____________________?

A. Evaporation and burning the concentrate followed by causticisation of products
B. Multi-effect evaporation only
C. Selective liquid extraction
D. Extractive distillation

A. Hydration
B. Decomposition
C. Oxidation
D. Reduction

A. Require lower initial investment
B. Require more power
C. Produce lower concentration NaOH
D. None of these

A. Calcium sulphate
B. Potassium sulphate
C. Potassium chlorate
D. None of these