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Chemistry

A Level

How can you work out, using the changes in oxidation numbers, which compound out of KCl, KBr and KI has the greatest reducing power?

We can work this out by observing the changes in oxidation state of sulphur in concentrated sulphuric acid (H₂SO₄) when this compound reacts with KCl, KBr and KI individually.
A...

Answered by Sarah P. • Chemistry tutor

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Explain what happens to a crystal of iodine when it is heated (5marks)

A crystal of iodine sublimes from its solid state to its gaseous state without turning into a liquid. Iodine forms a molecular covalent crystal. This means that there are strong covalent ...

Answered by Meghna I. • Chemistry tutor

23556 Views

Sodium chloride and sodium metal can both conduct electricity under differing conditions. Give the conditions required for each to conduct electricity and explain how each conducts electricity.

Sodium chloride will conduct electricity only when it is in a liquid state or in solution, this is because the ions are free to move in this state, allowing them to carry charge and conduct electricity. S...

Answered by Tanmayi J. • Chemistry tutor

36470 Views

How do I do redox calculations?

For example,Iron(II) sulphate can be oxidised using acidified potassium permanganate solution. Calculate the mass of iron(II) sulphate which will completely react with 200 cm3 of 0.25 mol l-1 acidified pe...

Answered by Collette G. • Chemistry tutor

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I don't understand how the first two quantum numbers fit into describing atoms.

There are 4 quantum numbers. Each one describes a specific electron's position relative to its nucleus.
The first one, "principal quantum number" describes the distance the talked about ele...

Answered by Nicole M. • Chemistry tutor

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