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Physics

How do you know the state an element at a certain temeperture?

By Niamh O'Sullivan
ChemistryGCSE

e.g. the melting point of hydrogen sulphide Is -85 degrees and its boiling point is -61 degrees.

1

Anything below its melting point is a solid.
Anything above its melting point and below its boiling point is a liquid
Anything above it boiling point is a gas
25 degrees is above the boiling point (which is -61 degrees)
So this must be a.........
Gas

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what is a alkali

By elliott heath
ChemistryGCSE
1

An alkali is a compound with particular chemical properties including turning litmus blue and neutralizing acids
An alkali has a pH of more than 7

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