Which of the following is true about indicators? question 20 options: they are weak acids or bases. they are as accurate as a ph meter. they maintain their colors across the range of ph values for which they are used. all of the above

Option (a) is the correct answer.

Explanation:

A substance that gives a visible change in color upon exposure to certain conditions is known as an indicator. Indicators are either weak acids or bases.

For example, phenolphthalein is an acid-base indicator which changes its color from colorless to pink in a basic solution at pH 8.2.

In a more basic solution, its color changes to bright purple.

Hence, indicators do not maintain their colors across the range of pH values for which they are used.

A pH meter tells exactly the pH value of a solution or substance. Whereas an indicator only tells whether a solution is acidic or basic.

Therefore, we can conclude that it is true about indicators that they are weak acids or bases.

it should be p1 v1 = p2 v2

that tool would be a compass