Indicate the colour changes for the following samples:

Sample	Indicator
Dilute sulphuric acid	Methyl orange
Moist ammonia gas	Phenolphthalein
Moist chlorine	Red litmus
Moist carbon dioxide	Blue litmus
Dilute magnesium hydroxide	Phenolphthalein
Lemon juice	Blue litmus
Vinegar (Acetic acid)	Blue litmus
Water into which SO2 gas has been bubbled for sometime	Phenolphthalein
Water containing Na2O	Phenolphthalein
Milk of magnesia	Methyl orange

You are given the following solutions:

Hydrochloric acid (HCl), sulphuric acid (H₂SO₄), nitric acid (HNO₃), acetic acid (CH₃COOH), sodium hydroxide (NaOH), calcium hydroxide [(Ca(OH)₂], potassium hydroxide (KOH), magnesium hydroxide [Mg(OH)₂] and ammonium hydroxide (NH₄OH). Give the colour change for each of these solutions with red litmus, blue litmus, phenolphthalein and methyl orange solutions.

Choose the olfactory indicators and give their characteristics: red cabbage extract, onion, vanilla extract, litmus, clove oil.

Take 5 ml hydrochloric acid in a boiling tube or a conical flask. Add a few pieces of zinc granules to it.

(a) What do you observe on the surface of zinc granules?
(b) Name the gas evolved.
(c) What happens when the above gas is passed through soap solution?
(d) What happens when a burning candle is brought near the gas filled tube?