(a) What is an acid-base indicator? Name the three common indicators used in chemistry laboratory.
(b) Name an acid-base indicator extracted from lichen.
(c) What colour does the methyl orange turn to when put in an acidic solution ?
State whether the following statements are true or false. Correct the false statements. [5 MARKS] (a) All substances are either acidic or basic. (b) A compound if acidic will turn all indicators red. (c) Lime water turns red litmus blue. (d) Common salt dissolved in water turns blue litmus red. (e) Phenolphthalein is a natural indicator.