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Chemistry

A Level

The reversible reaction 2 SO2 (g) + O2 (g) <-> 2 SO3 (g) has a delta H value of -197 kJ/mol. Use Le Chatelier's principle to explain what conditions would give the highest equilibrium yield and why industry uses different conditions. (5 marks)

Le Chatelier's principle states that if a system is disturbed - something changes - the system will tend to move in the direction that minimises the change. 3 marks from: The forw...

Answered by Conor C. • Chemistry tutor

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You are given a clear solution that is either an alkene or an alkane. Describe a test using bromine water that you could use to determine whether it is an alkene or alkane solution.

1 mark : Indication that the solution and bromine water should be mixed together1 mark : Indicating that the bromine water will de-colourise / go colourless if the solution contains an alkeneOR 1 mark awa...

Answered by Noah H. • Chemistry tutor

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Part a) Draw the mechanism of the attack of CN- on CH3COCH3 in the presence of HCN Part b) Explain why the product of this reaction does not rotate the plane of plane polarised light

Part a) 1 mark : Show the nucleophilic attack of CN- at the carbonyl forming the O-1 mark : Show the protonation of the O- via the deprotonation of HCNPart b)1 mark: Student has identified that the interm...

Answered by Noah H. • Chemistry tutor

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A chemist synthesised two solutions A and B, they know one solution is an aldehyde and the other a ketone. Suggest how the chemist could identify which is which and describe any observations they would make

Tollens reagent could be used to identify the the solutions A and B, as the aldehyde solution will oxidise to a carboxylic acid and a ‘silver mirror’ will be observed. Ketones cannot be oxidised further a...

Answered by Hugo J. • Chemistry tutor

1673 Views

Why is the Mg2+ ion smaller in radius than the Na+ ion?

The magnesium ion is in group two of the periodic table, whereas sodium is in group one. This means that magnesium has one more proton than the sodium ion, so it has a more positive core. Both ions have t...

Answered by Olivia D. • Chemistry tutor

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