Looking for Phenolphthalein 0.05% w/v?
We supply phenolphthalein 0.05% w/v in 2.5L containers, with discounts available on bulk orders over 4 items. Full MSDS is available to download from our website. We also offer many other options with all our products, from personalised labelling to bespoke chemicals.
Phenolphthalein as a pH Indicator: How Does it Work?
Phenolphthalein’s most popular use is as a pH indicator. It can be used by itself, or be an ingredient in universal indicators, alongside thymol blue or methyl red. These mixtures cover a wider range of pH changes.
From a chemical point of view, phenolphthalein works as a pH indicator due to 4 different states in solutions, with different colourations:
- In strongly acidic conditions (pH<1): orange colour
- In mildly acidic and near neutral conditions (0<pH<8.2): colourless
- In alkaline conditions (8.2<pH<12): pink
- In strongly alkaline conditions (pH>13): colourless
This compound has found its way into several colour-changing curious applications:
- When Barbie changes hair colour: Phenolphthalein is commonly used in toys, such as Barbie dolls and others, which involve a colour change. In this case, phenolphthalein is typically mixed with sodium hydroxide, which then can react with carbon dioxide in the air. This reaction results in a pH drop and Barbie can change her hair colour!
- Hard as concrete: This compound is also used to assess the quality of concrete. Under normal circumstances, concrete has a naturally high pH – around 8.5 – due to reaction with water. In this case, when a phenolphthalein solution is used, concrete turns bright pink. However, if this colour does not appear, it may be a sign of carbonation and deterioration.
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All our products come with 100% quality guarantee and are usually shipped within 24 hours after purchase. In addition to phenolphthalein, we also offer a wide range of other products, from pharmaceutical chemicals to specialist test kits. In addition, we also offer bespoke products to cover your needs. Simply contact us for further information.