Name an indicator which is pink in alkaline solution but turns colourless in acidic solution.

2 What colour do following indicators turn when added to an acid (hydrochloric acid)?

(a) litmus

(b) methyl orange

3 Name an indicator which is red in acid solution but turn blue in basis solution. 5 When a solution is added to a cloth strip treated with onion extract, then the smell of onion cannot be detected. State whether the given solution contains an acid or a base. 6 When a solution is added to vanilla extract, then the characteristic smell of vanilla cannot be detected. State whether the given solution is an acid or a base.