Give a chemical test to distinguish between:

(i) Ethane and ethene

(ii) Ethanol and ethanoic acid

(iii) Soaps and detergents.

(i) Ethene decolorizes the yellow colour of bromine water while ethane does not.

(ii) Ethanoic acid gives a brisk effervescence with sodium hydrogen carbonate while ethanol does not.

(iii) Soaps form curdy white precipitate or scum with hard water while detergents do not form any precipitate.