Question

2) What is the name of the indicator? | ઈન્ડીકેટરનું નામ શું
છે?​

Answer 1

Chemical indicator, any substance that gives a visible sign, usually by a colour change, of the presence or absence of a threshold concentration of a chemical species, such as an acid or an alkali in a solution. An example is the substance called methyl yellow, which imparts a yellow colour to an alkaline solution.

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