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The pH scale

Description

The pH of a substance can be found by dissolving a small amount of the substance in deionised water and adding a few drops of Universal Indicator solution. The colour produced is compared with a pH chart.

Type of Activity

:
demonstration, class practical

Audience

:
Teacher

Age Group

:
11 to 16 years

Credits

:
This resource has been provided by, or developed in partnership with, Nuffield Foundation
the-ph-scale



Apparatus Chemicals

Eye protection

Each working group (4 students) will require:

Test-tubes, 13 (Note 1)

Test-tube rack(s) with sufficient space for 13 test-tubes

Beakers (100 cm3), 2

Measuring cylinders (10 cm3), 2

Dropping pipettes (optional)

Deionised or distilled water

Dilute hydrochloric acid, 0.1 M

Dilute sodium hydroxide solution, 0.1 M

Universal indicator solution (HIGHLY FLAMMABLE), full range, ideally in small dropping bottles

pH indicator chart

Refer to Health & Safety and Technical notes section below for additional information.

 



 






Page last updated October 2015

The pH of a substance can be found by dissolving a small amount of the substance in deionised water and adding a few drops of Universal Indicator solution. The colour produced is compared with a pH chart.

ADDITIONAL INFORMATION

This is a resource from the Practical Chemistry project, developed by the Nuffield Foundation and the Royal Society of Chemistry. This collection of over 200 practical activities demonstrates a wide range of chemical concepts and processes. Each activity contains comprehensive information for teachers and technicians, including full technical notes and step-by-step procedures. Practical Chemistry activities accompany Practical Physics and Practical Biology .