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Flashcards in F324 part 1 Deck (46)
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1

Short hand notation for a fatty acid

A:B(C)
A = number of carbon bonds
B = number of double bonds
C = position(s) of double bonds

2

Equation for benzene reacting with chlorine

C6H6 + Cl2 --> C6H5Cl + HCl

3

Conditions for nitration of benzene

Conc. nitric acid, conc. sulphuric acid, 50ºC

4

Reaction of phenol and potassium hydroxide and organic product formed

C6H5OH + KOH --> C6H5O-K+ +H2O
Potassium phenoxide

5

3 common amines and short description

Amphetamine: treats daytime drowsiness and chronic fatigue syndrome
Phenylephrine: decongestant, in cold and flu medicine
Adrenaline: flight or fight hormone

6

Equation for propan-1-ol being fully oxidised

C3H7OH + 2[O] --(K2Cr2O7/H2SO4)--> C2H5COOH + H2O
heated under reflux

7

What reducing agent is used in the reduction of carbonyls

NaBH4

8

Observations for reaction of phenol with bromine

Bromine decolourises, white preciptate forms (2,4,6- tribromophenol)

9

Equation for ethanoic anhydride with methanol

(Ch3CO)2O + CH3OH --> CH3COOCH3 + Ch3COOH

10

Conditions for acid hydrolysis of esters

Heated under reflux with dilute sulphuric acid or dilute hydrochloric acid

11

Condition for oxidising primary alcohol to aldehyde

Distillation (prevents further reaction)

12

Name of product formed from bromine and cyclohexene

1,2- dibromocyclohexane

13

What is a nucleophile

An atom or group of atoms attracted for an electron deficient centre where it donates a pair of electrons, forming a covalent bond

14

Shape and bond angles around a carbon atom in a benzene ring

Triginal planar, 120º

15

Observation seen by acidified dichromate ions (colour change)

Orange to green

16

Product produced in the bromination of phenol

2,4,6- tribromophenol

17

How to identify a specific carbonyl compound

React with 2,4- DNPH, filter and recrystallise precipitate(purify), determine melting point and compare against known values

18

Observations of melted phenol and potassium

Potassium disappears, effervescence

19

Two ways to make esters

From carboxylic acids
From acid anydrides

20

Chemical test for an aldehyde/ Ketone and its observation

Brady's reagent (2,4- DNPH) orange precipitate

21

Why does alcohol dissolve in water?

Hydrogen bonds form between the polar OH grouop and water molecules

22

Why does benzene react with substitution reactions rather than addition reactions?

Subsition maintains the stability of the benzene ring. The product from an addition reaction would be less stable because the delocalisation in the ring structure would be lost

23

Reaction of methylamine as a base

Ch3H2N: + H^+ ---> [H3CNH3}^+

24

How to differentiate between an aldehyde and a ketone, with observations

Tollen's reagent:
Aldehye- forms silver grey solid, 'silver mirror'
Ketone- no reaction

25

Why should the reflux reaction for the nitration of benzene be kept below 50ºC ?

To stop multiple groups being substituted onto the benzene ring

26

Delocalised electron definition

An electron that's shared between more than two atoms

27

Method used to determine that benzene's bond lengths were all the same

X-ray Crystallography

28

Three pieces of evidence against the Kekulé model for benzene

1) All bond lengths are equal and intermediate between single and double C bonds
2) Less endothermic than expected (-208kjmol^-1)
3) Resistant to attack by bromine

29

What type of reaction is the formation of triglyceride

Esterification

30

Difference in structures of an aldehyde and a ketone

Aldehyde: C=O functional group at end of chain
ketone: C=O group at any point that's not the end

31

Compare bromination resistance between benzene, phenol and cyclohexene

- benzene electrons delocalized
-phenol O- lone paiir partially delocalised around ring
-cyclohenene electrons delocalised between 2 carbons
-Phenol and cyclohexene have a higher electron density than benzene
-Phenol and cyclohexene can both polaise Br2

32

Bromine and cyclohexene observation and equation

C6H10 + Br2 --> 1,2- dibromocyclohexane
Bromine goes colourless

33

Oxidising agent used int he preparation of carbonyls

Acidified potassium dichromate ions

34

Way to detect carbonyl group and observation

Brady's reagent (2,4- dinitrophenolhydrazine )
Aldehyde or ketone form a yellow/ orange precipitate

35

Type of reaction for the reduction of carbonyls

Nucleophilic addition

36

Conditions for preparing esters

-Carboxylic acids
react with an alcohol in an acid catalyst (heat)
-Acid anhydrides
heat gently with an alcohol

37

Three uses of phenol

Surfactants
Detergents
Antiseptics
Epoxy resin for paint

38

Observation of sodium and phenol

Effervescence (hydrogen gas)

39

Conditions for alkaline hydrolysis of esters

Heated under reflux with aq NaOH or KOH

40

How can aliphatic amines be prepared?

By warming halogenalkanes gently with an excess of ammonia (ethanol used as a solvent)

41

Equation for combustion of methanol (and state symbols)

CH3OH(l) + 1.5O2(g) --> CO2(g) + 2H2O(l)

42

Products forms from oxidising the three types of alcohols

Primary: Aldehyde then carboxylic acid
Secondary: Ketone
Tertiary: cant be oxidised

43

When does a coupling reaction occur?

When diazonium salt is reacted with a phenol or other aromatic compound

44

Example equations for how aluminium chloride can act as a halogen carrier catalyst

AlCl3 + Cl2 --> AlCl4^- + Cl^+
(electrophilic subsitution occurs)
H^+ + AlCl4^- --> AlCl3 + HCl

45

What is an electrophile?

An atom or group of atoms, attracted to an electron rich centre, which accepts a pair of electrons for form a new covalent bond

46

Why does bromine react more readily with phenol than with benzene

Higher electron density in phenol ring from the lone pair of electrons in the -OH group
- this causes bromine molecules to be more easily polarised and therefore more easily attracted