Amines;

Question 1

What are cationic surfactants?

Answer 1

= quaternary ammonium salts are used to make cleaning products
examples: shampoo, detwergent, washing liquid
= has a positive end and is attracted to a negative ion
= hydrocarbon tail- sationic surfactant

Question 2

How do thesec ationic surfactants works?

Answer 2

= non-polar tail,is attracted to the oil/grease
= polar head is attracted to the water
= allows water and oil to mix and removes grease
= have a positive ammoium ion that is attracted to the negativley charged fivres of hair remives static

Question 3

How are amines able to act as bases?

Answer 3

= nitrogen in amines have a lone pair of electrons- this is readily avaliable to act as an electron acceptor, by forming a dative covalent bond with H+ ions (protons)

Question 4

What does the strength of the base depend on?

Answer 4

= avaliability of the lone pair of electrons on nitrogen
= higher electron density the more avalibale the electrons are
= dependant on type of group

Question 5

What is the order of base strength?

Answer 5

= aromatic amines
= ammonia
= primary aliphatic amines
=

Question 6

Why is a aromatic amines a weak base?

Answer 6

= the lone pair of electrons on the nitrogen are are pulled away into the beneze ring structure
=electron density of nitrogen decreases
= less readily avaliable
= so less basic

Question 7

Why are alkyl groups a better base?

Answer 7

= electron donating, push electrons towards the nitrogen making it have a higher eletcron density so it is more readily avaliable as a base
= lone pair of electrons
=

Question 8

What are the 2 ways aliphatic amines can be made?

Answer 8

= reacting a haloalkane with excess ammonia
= reducing a nitrile

Question 9

How do we make aliphatic amines using haloalkanes and excess ammonia?

Answer 9

= nucleophilic addition- 2 moles of ammonia required
= this forms a primary amine is formed and Hydrogen halide
=

Question 10

What is the problem of the nucleophilic substituin reaction?

Answer 10

= can form primary, secondary teritary and quaternary salts
= impure
= occurs as primary amines have a lone pair of electrons on the nitrogen remaining so can also act as a nucleophile if there is an excess of haloalkane
= instead we use 2 amines rather than ammonia

Question 11

How do we reduce nitriles? using cataltytic hydrogenation

Answer 11

= using a nickel catalyst and hydrogen
= catalytic hydrogenation
= produces only primary amines
= uses 4[H]

Question 12

How do we reduce nitriles? - strong reducing agent

Answer 12

= using strong reducing agent, LiAlH
= and dilute acid
= more expensive than hydrogen gas, and nickel catalyst,
= reduction
=

Question 13

How do we make aromatic amines?

Answer 13

= reducing nitro compounds
= aromatic amines are used to make dyes, pharmecuticals
= heat under reflux, with concdnetrated HCL, and tin to form a salt- ammoium salt
= reacted with an alkali, such as NaOH, to prodice aromatic amine and water

Question 14

Identify a substance that could be added to aqueous butylamine to produce a
basic buffer solution.

Answer 14

= a strong acid, Hcl