Question

What are indicators?give examples of them and colours in acidic and basic solution.

Answer 1

Answer:Indicators

Name Acid Color Base Color

Bromocresol green Yellow Blue

Methyl red Red Yellow

Litmus Red Blue

Bromothymol blue Yellow Blue

Explanation:

Answer 2

Indicators:

• Indicators are substances that change colour when added to an acid or base.

• Some natural indicators are Litmus paper, phenolphthalein, methyl orange.

• In acidic medium, blue Litmus turns to red and Methyl orange turns to red.

• In basic medium, red Litmus turns to blue, Methyl orange turns to yellow and phenolphthalein turns to pink.

• Litmus solution is a purple dye which is extracted from lichen, a plant belonging to division Thallophyta.

• Olfactory indicators like vanilla extract and onion strips Changes odour in the presence of acidic medium.