Question

you are provided with three test tubes A,B and C

Test tube A Contains solution of tartaric acid

Test tube B contains soap solution

Test tube C contains pure water

what will you observe when you put

A piece of red litmus paper in each test tube

A piece of blue litmus paper in each test tube

A drop of phenolphthalein in each test tube







​

Answer 1

Answer:-

Given:

There are three test tubes A , B ,C ; containing tartaric acid , Soap solution & Pure water.

Also, red litmus, blue litmus & Phenolphthalein indicator are given.

Before testing the changes in the indicators, we have to keep in mind that,

For acid,

• The colour of blue litmus changes to red in acid.

• There will be no change in the red litmus if it is put in an acid.

• Phenolphthalein becomes colourless when it is put in an acid.

For a base ,

• There is no change in blue litmus if it is put in a base.

• The colour of red litmus turns blue if it is put in the base.

• Phenolphthalein changes to pink in a base.

Now,

Test tube - A contains tartaric acid.

As it is an acid ,

• Blue litmus changes to red.

• Phenolphthalein becomes colourless.

• There will be no change in the red litmus.

Test tube - B contains soap solution.

Soap solution is a base.

So,

• Red litmus turns blue.

• There will be no change in the blue litmus.

• As it is base , the colour of phenolphthalein changes to pink.

At last,

Test tube - C contains water.

Water is a neutral compound.

There will be no change in any of the indicators if water is added to them.

So, there will be no change in the three indicators.

Answer 2

1. Test Tube A : Tartaric Acid

• The red litmus Will not change it's colour
• The blue litmus changes to red
• The phenolpthelein becomes colourless

2. Test Tube B: Soap Solution:

• The red litmus Will change to blue
• The blue litmus Will not change
• The phenolpthelein becomes pink

3. Test Tube B: Pure water:

• The red litmus Will not show any change it's colour
• The blue litmus doesn't show any change
• The phenolpthelein doesn't change

━━━━━━━━━━━━━━━━

EXPLANATION:

• Celarly from name Tartaric acid is an Acid
• Soap Solution is Basic
• Pure water is neutral

Red Litmus:

• Changes to blue in basic solution
• Remains unchanged in Neutral and acidic solution

Blue litmus:

• Changes to red on acidic solution
• Remains unchanged in Neutral and basic solution

Phenolphthalein :

• changes to pink in a base.
• Becomes colourless in an acid.
• For neutral it doesn't change