Question

Neutral solutions which do not change the colour of either red/blue litmus are known as

Answer 1

Your answer is in the question which is

Neutral Solution

Answer 2

Neutral solutions which do not change the colour of either red/blue litmus are known as Non reacting solution. They have a pH of 7 and they are neutral in nature that is they are  having no effect on red or blue litmus paper. Example of a neutral solution is pure water. Now the point is the water that we consume is not neutral and is slightly acidic in nature due to pollution which results in the water reacting to traces of nitric oxide and sulphur dioxide present in nature.