19A.1

Question 1

what bond shape does amine do

Answer 1

trigonal pyramidal shape

Question 2

how many pair of electrons is in an amine and how many are paired and lone

Answer 2

3 paired pairs , and one lone pair (all from nitrogen)

Question 3

if there is one alkyl group attached in the amine it will be considered as

Answer 3

primary amine

Question 4

if there is two alkyl group attached in the amine it will be considered as

Answer 4

secondary amine

Question 5

if there is three alkyl group attached in the amine it will be considered as

Answer 5

tertiary amine

Question 5

what is an amine

Answer 5

nitrogen-containing compounds that have some similarities with ammonia

Question 5

what is the state of methylamine, ethylamine, propylamine, and butylamine at room temp

Answer 5

methyl is gas, ethylamine is gas with BP at 17c, and Propylamine and Butylamine are volatile liquids

Question 5

amines occur in

Answer 5

drugs, nature, and compounds called amphetamines

Question 6

what is the structural, displayed, and skeletal formula of amines

Answer 6

page 238

Question 7

how do you prepare aliphatic amines from halogenoalkane

Answer 7

by heating a halogenoalkane with ammonia, and since ammonia is a gas it will be done under pressure in a sealed container, alternatively it could be made by mixing the halogenoalkane with concentrated aq ammonia.

Question 8

what is the equation and type of reaction for the preparation of amines from halogenoalkanes

Answer 8

CH3Cl + NH3 —-> CH3NH2 +HCl this reaction is a nucleophilic attack by lone pairs of electrons of ammonia on the electron deficient carbon atom in the halogenoalkane

Question 9

how can a secondary amine form from the preparation of amines from halogenoalkanes

Answer 9

after a primary amine is formed from the nucleophilic reaction between ammonia and the halogenoalkane we notice that the nitrogen in the primary amine has a lone pair of electrons, so it would act as a nucleophile, competing with ammonia to react with the halogenoalkane forming a secondary amine.

Question 10

what is the equation for the formation of the secondary amine

Answer 10

CH2Cl + CH3NH2 —> (CH3)2NH + HCl

Question 11

how do we prevent unwanted side reactions ( formation of secondary amines) in the preparation of amine by halogenoalkane

Answer 11

by using ammonia in excess so that it outnumber the molecules of primary amines formed

Question 12

what is a batter way to represent the equation for the preparation of amine by halogenoalkane when we add ammonia in excess and why

Answer 12

CH3Cl + 2NH3 —> CH3NH2 + NH3Cl sine the excess ammonia would react with the acidic hydrogen chloride.

Question 13

how can we prepare aliphatic amines from nitriles

Answer 13

by reducing a nitrile using lithium tetrahydridoaluminate (LiAlH4) mixed in dry ether

Question 14

what is the the equation for the equation for the reduction of a nitrile to a amine

Answer 14

RCN + 4[H] —-> RCH2NH2

Question 15

why do we use dry ether for the reduction of nitriles into amines

Answer 15

to ensure no water effects the reaction

Question 16

how can we prepare Aromatic amines such as phenylamine

Answer 16

by reducing nitrobenzene.

Question 17

what is the reducing agent and how is the reduction of nitrobenzene to phenylamine take place

Answer 17

so the reducing agent is tin mixed with concentrated hydrochloric and is then heated under reflux with nitrobenzene, the reduction is achieved partly form the oxidation of tin to tin(II) ions and tin to tin(IV) ions and partly from the hydrogen produced from the reaction between tin and the acid.

Question 18

what is the equation for the reduction of nitrobenzene to form a amine

Answer 18

C6H5NO2 + 6[H] —-> C6H5NH2 + H2O

Question 19

what will happen to phenylamine once its formed form the reduction of nitrobenzene and why

Answer 19

it will react with the acid and form a phenylammonium ion since it is basic

Question 20

how can we convert phenylammonium ion to phenylamine + equation)

Answer 20

by just adding an alkali ( C6H5NH3^+1 + OH^- ——> C6H5NH2 + H2O

Question 21

what is phenylamine used for

Answer 21

1. manufacture of polymers
2. manufacture of pharmaceuticals
3. dyes used mainly for clothing (synthetic indigo blue colour in denim jeans)

Question 22

when naming nitriles what do we with the carbon number

Answer 22

so the code at the beginning (propane, butane) will be from all the carbons including the one attached to the nitrogen