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Phenolphthalein

en.wikipedia.org/wiki/Phenolphthalein

Phenolphthalein /ˌfiːnɒlfˈθeɪliːn/ is a chemical compound with the formula C20H14O4 ... This reaction leads to the pH falling below the color change threshold as h...

Why does phenolphthalein change color? | Reference.com

www.reference.com/science/phenolphthalein-change-color-e65f5390badb2cba

Phenolphthalein, which is an acid-base pH indicator, is a weak acid. For this reason, this indicator is colorless in the presence of acids that are also associated ...

Acid-Base Indicators - Chemistry Department - Elmhurst College

chemistry.elmhurst.edu/vchembook/186indicator.html

Whereas most dyes do not change color with the amount of acid or base present, there ... Phenolphthalein is an indicator of acids (colorless) and bases (pink).

Research the Topic - How does phenolphthalein work? Part 1

researchthetopic.wikispaces.com/How does phenolphthalein work? Part 1

Sep 30, 2011 ... Phenolphthalein has positively charged hydrogen ions. The reason phenolphthalein changes color is because although the phenolphthalein ...

Why Does Phenolphthalein Change Color? | eHow

www.ehow.com/how-does_5271431_phenolphthalein-change-color.html

About Phenolphthalein. Phenolphthalein is a mildly acidic compound that has a chemical formula of C20H14O4. It is primarily used as a pH indicator, allowing ...

Indicators

www.ch.ic.ac.uk/vchemlib/course/indi/

... (also known as pH indicators) are substances which change colour with pH. ... Phenolphthalein is a colourless, weak acid which dissociates in water forming ...

Why do we use phenolphthalein as an indicator in titration? - Quora

www.quora.com/Why-do-we-use-phenolphthalein-as-an-indicator-in-titration

Nov 25, 2015 ... Well, you may have used phenolphthalein as the indicator in a particular titration you ... From this exposure, we can of course testify to the color change property of phenolphthalein, recalling that its characteristic hue is a light ...

Indicators - Science

www.science.uwaterloo.ca/~cchieh/cact/c123/indicator.html

Indicators are substances whose solutions change color due to changes in pH. .... Phenolphthalein in the table above has a pKai value of 9.7, which is the ...

ACID BASE INDICATORS - Chemistry

chemistry.bd.psu.edu/jircitano/abindic.html

... (also known as pH indicators) are substances which change color with pH. ... Phenolphthalein is a colorless, weak acid which dissociates in water forming ...

BBC - GCSE Bitesize Science - Titrations : Revision

www.bbc.co.uk/schools/gcsebitesize/science/triple_ocr_gateway/how_much/titrations/revision/1/

Phenolphthalein changes colour sharply at about pH 8. For most purposes, this means that it is pink in alkaline solutions and colourless in acidic solutions.

Answer
Why Does Phenolphthalein Change Color?
Phenolphthalein is a chemical compound composed of 20 carbon molecules, 14 hydrogen molecules and 4 oxygen molecules. It is mildly acidic and is primarily used as a pH indicator. It is also sometimes used as a laxative, though its laxative effects are... More »
Difficulty: Easy
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What does phenolphthalein changing pink indicate? | Reference.com

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The addition of a base to a solution of phenolphthalein removes hydrogen ions from the solution, creating more phenolphthalein ions, which causes the color to  ...

acid-base indicators - Chemguide

www.chemguide.co.uk

You should be able to work out for yourself why the colour changes when you add an ... Phenolphthalein is another commonly used indicator for titrations, and is ...

Why does phenolphthalein change colour around pH 9.0 but methyl ...

www.quora.com

May 13, 2014 ... Indicators are chemicals whose chemical structures experience drastic changes when concentration of protons change. Some indicators ...