Question #04f3c

1 Answer
Aug 6, 2017

Formaldehyde is a naturally occurring organic compound with the formula CH2O

a)#"CH"_2"O(aq)" + "HCN(aq)" rarr "HOCH"_2"CN(aq)"#

As the carbonyl groups in aldehyde are polar because of the difference of electronegativity of the carbonyl carbon atom and oxygen they are both prone to electrophilic attacks at the oxygen atom and nucleophilic attacks at the carbonyl carbon atom.

The carbon acts as an electrophilic centre and the #"CN"^-# bonds. with it hence breaking the double bond between the oxygen.This makes the oxygen ion negative which attracts the hydrogen atom to bond with it.

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b)#"NH"_2"OH"#

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This is an electrophilic attack by 2 protons on a oxygen ion and this forms water which is good leaving group and so leaves the aldehyde. The #NOH^(-2)# takes its place and the nitrogen double bonds with the carbon.

#"CH"_2"O(aq)" + "NH"_2"OH(aq)" rarr "H"_2"CNO(aq)" + "H"_2"O"(l)#
This is how #"H"_2"CNO"# looks

web.pdx.edu

c) C2H5OH

Ethanol does not react with HCN. Did you mean "ethanal"?That's a different thing