Question

substances which are used tl test whether a substance is an indicator​

Answer 1

Answer:

Litmus

Explanation:

This method is called litmus test. Litmus is a chemical substance that is obtained from the Marine exclusive life forms called lichens. Lichens are the symbiotic relationship between fungi and cyanobacteria(blue green alga) . Litmus can be found in two forms which are litmus paper and litmus solution.