what is Phenolphthalein?

Question

Is it pH?

Answer 1

# a laxative used in many preparations under various trade names; also used as an acid-base indicator in titrations involving weak acids and strong bases because it is brilliant red at high alkalinity and colorless below pH 8
wordnet.princeton.edu/perl/webwn

# Phenolphthalein is a sensitive pH indicator with the formula C20H14O4. Often used in titrations, it turns from colorless in acidic solutions to pink in basic solutions, the color change occurring between pH 8 and pH 10. If the concentration of indicator is particularly strong, it can appear purple.
en.wikipedia.org/wiki/Phenolphthalein

Answer 2

The phenolphthalein is a substance used as an indicator in an acid base titration. It is not pH. pH is the Hydrogen potential of a substance it is the log of the molarity of hydrogen in a substance. Example: in pure water, the concentration of hydrogen atoms is 1.0*10^(-7) so the pH of pure water is 7. Phenolphthalein, to answer your question, is an indicator, a substance that changes color with is chemical environment. In a titration, a procedure in which involves acids and bases, each acid and base has a particular pH. Acids less than 7, Bases above 7. An indicator is added and depending on the pH of the reactants in the reaction it reacts. Phenolphthalein is colorless in an acidic environment (ph<7) and rose-red in a basic environment. That way, when in a titration, one can know the result of it, just by the color of the phenolphthalein. I hope that answers your questions ; )

Answer 3

Phenolphthalein is a sensitive pH indicator with the formula C20H14O4. Often used in titrations, it turns from colorless in acidic solutions to pink in basic solutions. If the concentration of indicator is particularly strong, it can appear purple.

In strongly basic solutions, phenolphthalein's pink color undergoes a rather slow fading reaction and becomes colorless again. In other words, the molecule has three forms:
H2Phenolphthalein
acidic
no color ↔ Phenolphthalein2-
basic
pink ↔ Phenolphthalein(OH)3-
strong alkaline
no color

The fading reaction is sometimes used in undergraduate classes for the study of reaction kinetics.

Phenolphthalein is insoluble in water, and is usually dissolved in alcohols for use in experiments. It is itself a weak acid, which can lose H+ ions in solution. The phenolphthalein molecule is colorless. However, the phenolphthalein ion is pink. When a base is added to the phenolphthalein, the molecule ↔ ions equilibrium shifts to the right, leading to more ionization as H+ ions are removed. This is predicted by Le Chatelier's principle.

Answer 4

Phenolphthalein is a sensitive pH indicator with the formula C20H14O4. Often used in titrations, it turns from colorless in acidic solutions to pink in basic solutions. If the concentration of indicator is particularly strong, it can appear purple.

In strongly basic solutions, phenolphthalein's pink color undergoes a rather slow fading reaction and becomes colorless again. In other words, the molecule has three forms:

H2Phenolphthalein
acidic
no color ↔ Phenolphthalein2-
basic
pink ↔ Phenolphthalein(OH)3-
strong alkaline
no color

The fading reaction is sometimes used in undergraduate classes for the study of reaction kinetics.

Phenolphthalein is insoluble in water, and is usually dissolved in alcohols for use in experiments. It is itself a weak acid, which can lose H+ ions in solution. The phenolphthalein molecule is colorless. However, the phenolphthalein ion is pink. When a base is added to the phenolphthalein, the molecule ↔ ions equilibrium shifts to the right, leading to more ionization as H+ ions are removed. This is predicted by Le Chatelier's principle.

Answer 5

phenolphthalein is an indicator used to show the general pH of a solution. around a pH of 7 or 8, phenolphthalein will ionize and turn pink, indicating the change in pH.

Answer 6

It's an indicator. It has no pH. It will reflect the pH of the solution during titration. When the pH of the solution is out of its range, there will be no change.

Then you know you should have used methyl orange for the titration!

Answer 7

Laxative, carcinogen, and commonly used titration indicator.

At a certain pH it changes color. pH is a measure of the acidity, so therefore this indicator can tell you when you have a change in pH within the range which changes this compounds color.

Answer 8

I will add that a good way to remember which end of the pH scale is which color is "basic becomes blue". This helped me in freshman chemistry.

Answer 9

This is a chemical that is used when titrating a liquid substance. It indicates when a liquid has become a base. Only a tiny amount is needed and then when you titrate it, it becomes pink when the liquid becomes a base.