Rain falling to earth as a weak acid reaches the tap as a solution of ionic compounds. Soap reacts with these compounds to form insoluble calcium soap, precipitated as scum, while soapless detergents form soluble acid salts. Gives an explanation of water softening by ion exchange.
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How to watch
Collection
In ACMI's collection
Credits
Collection metadata
ACMI Identifier
321172
Language
English
Subject categories
Climate, Environment, Natural Resources & Disasters → Water
Climate, Environment, Natural Resources & Disasters → Water - Analysis
Climate, Environment, Natural Resources & Disasters → Water quality
Communications, Infrastructure, & Transport → Water
Communications, Infrastructure, & Transport → Water - Analysis
Documentary → Documentary films - Great Britain
Educational & Instructional → Educational films
Mathematics, Science & Technology → Chemical elements
Mathematics, Science & Technology → Chemical reactions
Sound/audio
Sound
Colour
Colour
Holdings
16mm film; Access Print (Section 1)