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Chemistry

A Level

Explain what the rate-determining step in a reaction is with reference to activation energy.

The rate determining step is the slowest step in a multi-step reaction, and it is the step in the reaction with the highest activation energy. It is the step in the reaction which decides the overall rate...

Answered by Sammy A. • Chemistry tutor

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When propanal is reacted with potassium cyanide under weakly acidic conditions the resulting mixture does not rotate plane polarised light. Explain this observation.

A common mistake is to answer this question with the explanation that the light is not rotated because no optical isomers are present. However, this is incorrect. The only other time where plane polarised...

Answered by Sally D. • Chemistry tutor

5079 Views

Periodicity shows a fairly smooth increasing trend across a period for ionisation energy. However, between groups 2 & 3 and groups 5 & 6, the trend doesn't appear to be followed. Using your knowledge of chemistry, explain why the trend isn't followed here

For elements in group 2, their valence electrons consist of "ns²" where n is the principle quantum number/shell number. However, for elements in group 3, their valence electrons consi...

Answered by George W. • Chemistry tutor

2016 Views

Draw the full structual diagram of ethyl-ethanoate, labeling relevent bond angles and explain why the molecule has this structure.

(unable to draw diagram and upload in this format) ethyl ethanoate has the semi structural formula of CH3COOCH2CH3. According to electron repulsion theory the bond angle around the second carbon atom woul...

Answered by • Chemistry tutor

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Plan out a 4 step organic synthesis to form N-methyl Butanamide from 1-Bromopropane. Include relevant reagents and conditions for each reaction. Include 1 mechanism for one of the stages.

The chain length needs to be extended by 1, so we can use NaCN dissolved in ethanol to extend the carbon chain by 1. This will produce butanenitrile. Mechanism here.2) Now that the ...

Answered by George W. • Chemistry tutor

3387 Views