pH indicators change the color depending upon acidity or basicity.
Litmus paper: red color in acidic solutions and blue color in basic solutions.Phenolphthalein: no color in acidic solutions.
If phenolphthalein is added to HBr (hydrobromic acid), which is a strong acid, the phenolphthalein indicator will remain colorless because it only changes color in the presence of a base. Since HBr is an acid, it will not cause the indicator to change color.
An acid base indicator is a chemical substance that has the ability to change color depending on the pH.
Red litmus paper stays red in the presence of an acid and turns blue in the presence of a base. Blue litmus paper stays blue in the presence of a base and turns red in the presence of an acid.
You use the blue litmus to to test an acid other wise no result of testing an acid
It should be clear. Phenolphthalein doesn't change color in the presence of an acid, only a base.
Acid-base indicators are used for this purpose.
Litmus paper: red color in acidic solutions and blue color in basic solutions.Phenolphthalein: no color in acidic solutions.
pH indicators change the color in contact with acids or bases.
When litmus paper touches an acid, the paper changes to red. When it touches a base, the paper changes to blue. By comparing the color the litmus paper changed to by a chart, you could determine how strong or weak that acid or base is.
This indicator changes his color.
Indicators are chemicals that change color in the presence of an acid or a base. The most commonly used indicator is phenophthalein.
Blue litmus turns red in the presence of an acid and remains blue in the presence of a base.
an indicator
Bromothymol blue (BTB) turns yellow in the presence of an acid and blue in the presence of a base.
depends on the indicator used. in case of red litmus... changes to blue for basesand no change in acids blue litmus - changes to red in acids, no change in bases phenolpthelin - changes to pink in bases, no change in acid methyl orange - changes to red in acids and yellow golden in bases
Recreation of an indicator using an acid and a base involves mixing a colorless or faintly colored acid-base indicator with an acid to make the solution acidic (and change color) and then adding a base to neutralize the acid and return the indicator to its original color. This process demonstrates the reversible nature of acid-base indicators and how they can be used to visually indicate the presence of acids or bases in a solution.