Paper 2 ehaiblv

Question 1

What are the conditions for NaBH4 usage?

Answer 1

Aqueous ethanol

Question 2

Why are ketones less reactive than aldehydes?

Answer 2

The havea bigger inductive effect from adjacent alkyl groups and so this reduces the d+ on the C bond.

Question 3

What is used as a catalyst for the reaction of an alcohol and a carboxylic acid to produce an ester.

Answer 3

Concentrated H2SO4.

Question 4

What are 4 uses of esters?

Answer 4

Solvents, plasticisers, perfumes and food colouring.

Question 5

What solution does acid or base hydrolysis of esters occur in?

Answer 5

Aqueous solution.

Question 6

What is biodiesel made of?

Answer 6

Methyl esters and long chain carboxylic acids.

Question 7

How is biodiesel made?

Answer 7

Reacting triglycerides with methanol in the presence of an alkali catalyst such as NaOH.

Question 8

What does the gradient represent on a graph of log(rate) against log(Y)?

Answer 8

The order of the reactant.

Question 9

What does the y-intercept reresent on a graph os log(rate) against log(Y)?

Answer 9

Log(K)

Question 10

What can be calculated from the gradient of a graph of 1/T against ln(rate)?

Answer 10

The activation energy. (x 8.31)

Question 11

What are the conditions for oxidation of aldehydes or ketones with K2Cr2O7?

Answer 11

heat under reflux

Question 12

Give two ways carbonyls can be reduced?

Answer 12

NaBH4 in aqueous ethanol or H2 and a Ni catalyst.

Question 13

What are the reactants and conditions for the formation of hydroxynitriles from carbonyls?

Answer 13

NaCN and dilute sulfuric acid.

Question 14

What does the nucleophilic addition of CN- to a carbonyl produce?

Answer 14

A racemic mixture of hydroxynitrililes

Question 15

What are carboxylic acids strong enough to do?

Answer 15

Displace CO2 from carbonates.

Question 16

Why is dissociation of carboxylic acids likely?

Answer 16

The salts are stabilised by delocalisation.

Question 17

Why can methanoic acid be oxidised?

Answer 17

It has effectively an aldehyde group.

Question 18

What is needed for a carboxylic acid to react with an alcohol and what is produced?

Answer 18

An ester and water, requires a strong acid catalyst.

Question 19

What are the conditions for hydrolysis of an ester?

Answer 19

Dilute acid, heat under reflux.

Question 20

Does the reaction of an ester with a dilute acid or dilute NaOH co to completion?

Answer 20

NaOH, reaction is not reversible.

Question 21

What are soaps?

Answer 21

long chain carboxylic acids, produced by the hydrolysis of fats.

Question 22

What is aspirin made from?

Answer 22

2-hydroxybenzoic acid.

Question 23

Why may there be a loss of yield when making aspirin by recrystallisation?

Answer 23

-crystals lost in filtration or washing, some product stays in solution after recrystallisation or other side reactions occur.

Question 24

What is the H-C-C bond angle in benzene?

Answer 24

120

Question 25

When is the name phenyl- used?

Answer 25

When benzene ring is regarded as a substituent side group.

Question 26

Why si the nitration of benzene important

Answer 26

Explosives manufacture and formation of amines for use in dyes.

Question 27

Whata re the conditions of the friedel crafts acylation?

Answer 27

Heat under reflux with acyl chloride in the presence of anydrous aluminium chloride catalyst.

Question 28

Why are friedel-crafts reacyions important?

Answer 28

Introduces a reactive group onto the benzene ring.

Question 29

What is LiAlH4 used for?

Answer 29

Reduction, reducing agent. W

Question 30

What is required for dehydration of alcohols?

Answer 30

H2SO4

Question 31

What do amines as bases react with acids to produce?

Answer 31

Ammonium salts.

Question 32

Addition of what to an ammonium salt will convert it back to the amine?

Answer 32

NaOH

Question 33

Gve two ways amines cane be prodced from nitriles.

Answer 33

Nucleophiliic substitution with a haloalkane. | Convert haloalkane to nitrile with KCN in ethanol (heating under reflux). REduce the nitrile using LiAl4 in ether.

Question 34

What is TLC?

Answer 34

Plat is coated with a solid and solvent moves up the plate.

Question 35

What is CC?

Answer 35

A column is packed with a solid and a solvent moves down the column.

Question 36

What is GC?

Answer 36

A column is packed with a solid or solid coated by a liquid, has is passed through the column under high pressure and temp.

Question 37

What must the gas be in in GC?

Answer 37

Inert eg H2 or N

Question 38

What is GC used for?

Answer 38

Seperating volatile liquids.

Question 39

Why would mass spec not work on isomers?

Answer 39

They have the same M/z value.

Question 40

What is reflux?

Answer 40

The continuous evaporation and condensation of a mixture of liquids heated to the boiling point for a long period of time.

Question 41

What is the bond angle in cyclohexane?

Answer 41

109

Question 42

Why do different amino acids have different Rf values?

Answer 42

Different polarities distance moves is specific to the polarity.

Question 43

What is required for the nucleophilic substitution of bromoethane to produce ethanamine?

Answer 43

Ethanolic solvent.

Question 44

Why can primary amines react to form quarternary ammonium salts?

Answer 44

Each organic product is a stronger nucleophile than the reagent that made it,

Question 45

What is the stationary phase and what is the developing agent for TLC/

Answer 45

SiO2 and ninhydrin or UV light.

Question 46

Name 4 solvents used in NMR.

Answer 46

D2O, CCl4, CDCl3, C6D6.

Question 47

What is the bonding between polymer chains?

Answer 47

Van der Waals.

Question 48

How can u convert nitrobenzene to aminobenzene?

Answer 48

Add HCl and Sn under reflux then add NaOH at room temp.