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Chemistry

A Level

Why do certain metals give off different colours when heated?

This is to do with the electrons in the metal atoms. When a piece of the metal is heated, if there is enough energy supplied to the atoms, their electrons are excited and are promoted (jump up) to higher ...

Answered by Josh R. • Chemistry tutor

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How can you determine the shape of water?

Water consists of two hydrogen atoms covalently bonded to an oxygen atom, the atoms oxygen has 6 outer shell electrons, and wach hydrogen donates one, this results in the structure having 8 electrons, mea...

Answered by JOSHUA M. • Chemistry tutor

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What are the oxidation numbers of each element in these examples: a) H2SO4 b) N2 c) NH4+

a) H₂SO₄ANSWER: H: +1 S: +6 O: -2 b) N₂ANSWER: N: 0 (all elements not within a compound have an oxidation number of 0 eg I₂, O₂, K) c) NH₄

Answered by Georgia B. • Chemistry tutor

2207 Views

Would you expect a calcium ion to be bigger, smaller or the same size as a calcium atom? Give TWO reasons to explain your answer.

Calcuim is in group two which means when it forms an ion it will donate its two outer elections, this means a calcium ion will be smaller as it has one less shell of electrons.

Answered by Urma C. • Chemistry tutor

14517 Views