Question

What are olfactory indicators? Name two olfactory indicators, two natural indicators and two synthetic indicators.

Answer 1

Olfactory Indicators are used in laboratory for testing acid and base by changing the odours.For example,onion,clove oil,vanilla

Natural Indicators-turmeric,litmus

Synthetic Indicators- Phenolphthalein,methyl orange

Answer 2

Answer:

Olfactory indicators are those indicators that help to identify whether the given solution is acidic or basic by changing their smell instead of colour as other indicators do. Vanilla, clove and onion are all olfactory indicators as these do not give their distinct odour in highly alkaline(basic) medium.

olfactory indicators-Onion and vanilla extract 

natural indicators-red cabbage, turmeric, 

synthetic indicators-phenolphthalein and methyl orange.

Hope it helps