Phenolphthalein 1%

Phenolphthalein 1%



From: £21.67

Select Quantity:
  • Product Information
  • Specification
  • MSDS
  • B2B Note
  • More Options
  • Questions & Answers


Need Phenolphthalein 1%?

  • We supply phenolphthalein in 500ml containers, with discounts available for bulk orders
  • This is our most popular phenolphthalein product, but we also offer a 0.05 w/v solution
  • We also offer more options with all our products, from customised labelling to specific pack sizes
  • Simply contact us for further information or free technical advice

A popular pH indicator

With the formula C20H14O4, phenolphthalein is a common pH indicator, turning colourless in acidic solutions or pink in alkaline solutions. As such, it’s very popular to titrate acid-base reactions. This compound is insoluble in water and is typically prepared in alcohol solutions.

It works because the molecule version is colourless, but the ionic version is pink. When a base is added to the solution, the balance between molecule and ions is altered towards the ionic side, resulting in more H ions being removed from the molecule (with the subsequent production of phenolphthalein ion, which is pink). As a result, for pH below 8.2, the solution is colourless, but changes to pink when pH reaches 10.

Other uses

Despite being a popular pH indicator, this compound can be used in other applications:

  • Used for many years as a laxative, but its popularity is decreasing over fears of being carcinogenic after prolonged use
  • Also used in the Kastle-Meyer test to identify the presence of blood. In this case, a sample suspected of containing blood is treated with alcohol and phenolphthalein, followed by a few drops of hydrogen peroxide. If the sample contains haemoglobin, it turns pink. This is commonly used as a first analysis for its easiness, with the added bonus of not destroying the sample, which can later be used for other tests.

Friendly customer service team

We’re are very proud of our excellent customer service team. If you need assistance, simply contact us for advice. A member of staff will be available to help you before, during and after your order to ensure our product meets your needs.


MSDS Files

The following files are available to download:

Product ID Product post_status Bulk Download SDS File
3583 Phenolphthalein 1% publish 1319 - 1319 - SDS10106.pdf

Please note: we only deliver to registered UK businesses at non-residential addresses with a minimum order value of £100 before VAT

We only supply to mainland UK, contact us on 0800 990 3258 for rates to Ireland.

Please notify us if you have specific delivery requirements such as restricted access, requirement for a tail-lift delivery vehicle or pallet truck. Failure to notify us of a special delivery instructions can incur additional charges from our carriers.

Looking for further options on this product?

  • Custom packaging
  • Personalised labelling
  • Specific pack sizes
  • Different grades available
  • Bespoke blending
  • Bulk quantities

Call 0800 990 3258 for details or Contact Us

Questions and answers of the customers

There are no questions yet, be the first to ask something for this product.

Only registered users are eligible to enter questions

0800 990 3258