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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

20366 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

31503 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

2207 Views

Calculate the percentage of Copper in Copper oxide (CuO, Mr=80). (3 marks)

Ar of Cu = 64 (1 mark) Percentage of copper in CuO = 64/80 x100 (1 Mark) Percentage of copper in CuO = 80% (1 mark)

Answered by Katie D. • Chemistry tutor

22065 Views

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

2089 Views