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Chemistry

GCSE

A compound being analysed has the percentage composition by mass Ca = 13.9%, W = 63.9%, O = 22.2%. Calculate the empirical formula of this compound

Using rows to represent mathematical operations and a column for each compound we can draw ourselves a table:

Ca W O
% 13.9 ...

Answered by Haydn D. • Chemistry tutor

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How can I work out whether a hydrocarbon is an alkene or an alkane from its molecular formula?

Step 1:

Look at the molecular formula of the hydrocarbon you have been given.
(This is the formula that tells you exactly how many hydrogens and ...

Answered by Alice H. • Chemistry tutor

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Diamond and Graphite are both giant covalent structures. If they are both made of carbon why does diamond have a higher melting point?

Although both are giant covalent structures, they have different structures. Diamond makes a 3d structure with each carbon attached to 4 other carbons so the only bond to break when melting it is the very...

Answered by Zia F. • Chemistry tutor

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How is pure copper extracted froms it ore?

Answered by Gatsby F. • Chemistry tutor

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Calculate the atom economy of the following equation, assuming that KNO3 is the desired product. KOH + HNO3 ---> KNO3 + H2O (Mr of reactants and products, KOH - 56.1, HNO3 - 63.0, KNO3 - 101.1, H2O - 18.0)

Answer: 84.9% The equation for calculating the atom economy is = (Mr of desired product / total Mr of products) x 100 or = (Mr of desired product / total Mr of reactants) x 100 as the total Mr of the prod...

Answered by Manon S. • Chemistry tutor

3933 Views