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What product would you expect to obtain when reacting ethanal (or acetaldehyde) with potassium cyanide (KCN) in dilute acid? Draw a curly arrow mechanism for this transformation, and determine whether you obtain one enantiomer or a racemic mixture.

The product obtained is a cyanohydrin, with the formula CH3CH(OH)(CN) where the cyanide anion has acted as a nucleophile towards the aldehyde. The mechanism would first show the lone pair on the carbonyl ...

Answered by Alex S. • Chemistry tutor

2559 Views

Translation occurs in living cells. Explain how translation is carried out, from the initiation stage onwards.

Translation is the process where mRNA in the cytoplasm becomes a functional protein. Translation follows transcription, where an mRNA for a protein-coding gene is made. The mRNA leaves the nucleus through...

Answered by Tessa M. • Biology tutor

4210 Views

Explanation of the lac operon, based on 9700/41/M/J/18 Question 3

It is made up of 3 genes: lacZ, lacY and lacA which encode for B-galactosidase (LacZ), lactose permease (LacY), and another enzyme (not studied at A level) respectively.The functions of LacZ (the enzyme) ...

Answered by Jose V. • Biology tutor

3550 Views

Describe and evaluate research into obedience.

Obedience is following the orders of an authority figure and has been the subject of much research. Milgram (1963) wanted to look at how so many people were capable of doing horrible things to other peopl...

Answered by Phoebe G. • Psychology tutor

13437 Views

There are five main areas a duty of care may arise regarding omissions. Discuss any three areas.

Occasionally an omission can amount to an actus reus of a crime. An omission is a failure to act where there is a duty to act. In the UK the general rule regarding omissions is that there is no good Samar...

Answered by Marcello A. • Law tutor

4620 Views