Question

What are the physical tests to find out whether a substance is an acid or a base ?

Answer 1

There are many test which distinguish between acid or base. Mainly, litmus paper or litmus solution test is used to check whether the given substance is acidic or basic. If Litmus solution turn blue litmus red hence it is an acidic solution while if it turns red litmus blue hence it is a basic solution. Another way to obtain the objective is by pH paper or solution. If the observed colour lies in the range of 0–7 then it is an acid while if it lies in between 7–14 it is a base.

Answer 2

litmus paper test,
pH paper test