chem module 6 definitions

Question 1

aromatic compound

Answer 1

a compound containing at least 1 benzene ring

Question 2

electrophyllic substitution

Answer 2

a reaction in which an electrophile (an electron pair acceptor)
reacts with another compound to replace an atom / group of atoms

Question 3

2,4-dinitrophenylhydrazine

Answer 3

also known as Brady’s reagent, this compound forms an
orange precipitate in the presence of aldehydes and ketones. The melting point of the
2,4-DNP derivative of a carbonyl can be used to identify the carbonyl compound.

Question 4

aldehyde

Answer 4

compound containing a c=o bond on the carbon 1 atom. can be oxidised further

Question 5

ketones

Answer 5

compound containing c=o bond on a carbon bonded to 2 other carbonds. cannot be oxidised further

Question 6

nucleophile

Answer 6

electron pair donor

Question 7

nucleophilic addition

Answer 7

a reaction in which an electrophilic π bond reacts with a nucleophile,
breaking the π bond and forming 2 new σ bonds. Examples include carbonyl compounds
reacting with NaBH4
to form alcohols or with HCN to form hydroxynitriles

Question 8

Tollens reagent

Answer 8

also known as ammoniacal silver nitrate, this reagent forms a silver mirror
in the presence of an aldehyde and can be used to distinguish between aldehydes and
ketones. An aldehyde is oxidised to a carboxylic acid while silver ions in Tollens’ are reduced
to silver