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 intermediate has a trigonal planar structure1 mark: Student has detailed that the nucleophile (CN-) can attack from either side1 mark: A racemic mixture or 50:50 split of enantiomers that rotate light in opposite directions has been formed leading to no overall effect on the plane of plane polarised light.