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Acids and Alkalis
When a substance dissolves in water,
the solution may be acidic, neutral or alkaline.
What is an Acid?
defined an acid is any substance that produces
H+ ions or H3O+ ions in water.
Compare this with the definition of an alkali or base.
H+ ions are called hydrogen ions,
H3O+ ions are called hydroxonium ions.
You will mostly see acids in reactions
In reality, H+ is a single proton, and does not exist on its own.
It always attaches to something.
In water it joins to H2O to form H3O+ ions.
website will use either H+(aq) or H3O+(aq)
to mean acid in water.
An acid has a pH of less than 7.
See examples of acids, properties of acids and uses of acids.
See also Lowry and Brønsted.
Links Acids Revision Questions
gcsescience.com The Periodic Table Index Acid Quiz gcsescience.com
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