An acid-base indicator measures the pH of a solution of different substances.
The solution of the universal indicator exhibits several color changes from the range of 1-14 in the pH scale.
Any solution that has a pH value lower than 7 is considered to be acidic according to the pH scale. A solution is considered basic if its pH value is higher than 7.
When the colour of the solution turns red, an acidic dilution has occurred. And it is referred to as a basic solution when the colour is blue.
In neutral and acidic solutions the colour of the turmeric remains the same, in basic solutions, it turns bright red.