Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

adv higher chemistry > unit 2a: synthesis > Flashcards

unit 2a: synthesis Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

homolytic fission

A

involves the bond breaking evenly, meaning one electron from the shared pair in the bond goes into each atom, usually occurs in non-polar bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

free radicals

A

the result of homolytic fission, highly reactive species with unpaired electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

heterolytic fission

A

involves the bond breaking unevenly- with one atom getting both electrons from the bond and the other getting none, usually occurs in polar bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

result of homolytic fission

A

free radicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

result of heterolytic fission

A

positive and negative ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

curly arrow notation

A

used to show the movement of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

a single headed arrow

A

represents the movement of a single electron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

a double headed arrow

A

represents the movement of a pair of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

two categories of attacking groups

A

electrophiles and nucleophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

electrophiles

A

atoms or groups of atoms which are deficient in electrons, usually have a positive or partial positive charge and are able to accept electrons, they are attracted to a region of negative charge or groups that can donate electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

electrophile examples

A

Na^+, Mg^2+, NH4^+, NO2^+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

carbocations

A

positive carbon based ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

nucleophiles

A

atoms or groups of atoms which are rich in electrons, usually have a negative or partial negative charge or lone pairs and are able to donate electrons, they are attracted to a region of positive charge or groups that can accept electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

nucleophile examples

A

Cl^-, CN^-, H2O, C=C, OH^-, NH3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

elimination reactions

A

when atoms are removed from a molecule and a double bond is formed, they are the opposite of addition reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

substitution

A

when an atom or functional group is replaced by a different atom or functional group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

three types of substitution

A

free radical, electrophilic, nucleophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

free radical substitution

A

when UV light is used to trigger a free radical chain reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

electrophilic substitution

A

when an electrophile attacks a compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

nucleophilic substitution

A

when a nucleophile attacks a compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

monohaloalkanes can be made by

A

reacting alkanes with a halogen (free radical substitution), reacting a hydrogen halide with an alkene (addition), synthesised from alcohols

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

addition

A

a reaction where a small molecule adds onto an unsaturated molecule by reacting with the C=C double bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

condensation

A

a reaction where two molecules combine to form a larger molecule, by eliminating a smaller molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

hydrolysis

A

a reaction where a molecule is broken down, by reaction with water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

oxidation

A

oxidation causes and increase in the oxygen to hydrogen ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

reduction

A

reduction causes a decrease in the oxygen to hydrogen ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

neutralisation

A

a reaction between an acid and a base, most examples involve carboxylic acids reacting with bases, e.g. alkaline hydrolysis of fats/oils using sodium hydroxide in the making of soaps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

haloalkanes and nucleophilic substitution

A

the carbon - halogen bond is highly polar, the carbon is partially positive so it can be attacked by a nucleophile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

the two nucleophilic substitution mechanisms

A

Sn1, Sn2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Sn2 is undergone by

A

primary and secondary haloalkanes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

process of Sn2

A

the rate determining step (two molecules), transition state/activated complex, final molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Sn1 is undergone by

A

tertiary haloalkanes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

process of Sn1

A

rate determining step (one molecule), final molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

reasons for primary and secondary undergoing Sn2 and tertiary undergoing Sn1

A

steric hindrance, carbocation stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

steric hindrance

A

in primary and secondary haloalkanes there is space for the nucleophile to attack the carbon, in tertiary there is not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

carbocation stability

A

tertiary carbocations are more stable due to inductive stability therefore can exist long enough to undergo Sn1

37
Q

haloalkanes into alcohols

A

nucleophilic substitution using a base in water

38
Q

haloalkanes into ethers

A

nucleophilic substitution using alkoxides

39
Q

haloalkanes into nitriles into carboxylic acids

A

nucleophilic substitution using sodium cyanide in ethanol and react nitrile with aqueous acid

40
Q

monohaloalkane and elimination

A

react monohaloalkane with a strong base (NaOH) in ethanol, the halogen atom and a hydrogen atom on adjacent carbons are removed and an alkene is formed

41
Q

making alkenes

A

dehydration of alcohols (catalyst), base induced elimination of hydrogen halides from monohaloalkanes

42
Q

markovnikovs rule

A

when an unsymmetrical molecule is added to an unsymmetrical alkene, the hydrogen atom becomes attached to the carbon with the most hydrogens already attached

43
Q

why are two products make in alkene synthesis

A

stability of the carbon intermediate, secondary carbocation is much more stable so will occur more often

44
Q

forming monohaloalkanes with hydrogen halides from alkenes

A

electrophilic addition with a hydrogen halide added to a double bond

45
Q

forming alcohols with water from alkenes

A

adding water to alkenes uses water with electrophilic addition using an acid catalyst (HCl)

46
Q

forming dihaloalkanes with halogens from alkenes

A

electrophilic addition when a halogen molecule is reacted with a double bond

47
Q

forming alkanes with hydrogen from alkenes

A

electrophilic addition by adding hydrogen to an alkene, nickel catalyst is required

48
Q

three ways of making alcohols

A

substitution of haloalkanes, acid catalysed hydration, reduction of carbonyl compounds

49
Q

reduction of carbonyl compounds

A

alcohols are produced by this using a reducing agent e.g. LiAlH4

50
Q

aldehydes are reduced to

A

primary alcohols

51
Q

alcohols reaction with carboxylic acids

A

alcohols react to form esters, water is eliminated. conc. sulphuric acid is a catalyst

52
Q

alcohols reaction with acid chlorides

A

esters are formed and a condensation reaction takes place

53
Q

three ways of making carboxylic acids

A

oxidation of primary alcohols and aldehydes, hydrolysis of nitriles, hydrolysis of esters or amides

54
Q

hydrolysis of esters and amides to carboxylic acids

A

carboxylic acids can be prepared by hydrolysis of esters, acid catalyst is required

55
Q

four main carboxylic reactions

A

condensation with alcohols, reduction, reactions with metals/bases, reaction with ammonia/amines

56
Q

carboxylic reactions with metals/bases

A

forms salts

57
Q

carboxylic reactions with ammonia/ amines

A

forms amides when heated

58
Q

five main reactions of alcohols

A

dehydration, reactive metals, oxidation, condensation with carboxylic acids, condensation with acid chlorides

59
Q

ethers

A

organic compounds with general formula R-O-R’ where the Rs are alkyl groups

60
Q

ethers uses

A

solvents as they are relatively inert

61
Q

ethers properties

A

bp lower than their isomeric alcohol, soluble in water unless larger

62
Q

amines

A

related to ammonia where one or more hydrogens are replaced by alkyl groups

63
Q

amines properties

A

primary and secondary both contain the N-H bond so can form hydrogen bonding, lower bp for tertiary amines, soluble in water

64
Q

amine reactions

A

mainly react with acids since they are bases to forms salts

65
Q

aromatics structure

A

contain a benzene ring, when a hydrogen is replaced by another group this is called a phenyl group

66
Q

aromatic reactions

A

benzene can undergo electrophilic substitution, the 4 types are: halogenation, nitration, sulfonation, alkylation

67
Q

aromatic halogenation

A

react benzene with chlorine and a hydrogen is substituted with a chlorine atom

68
Q

aromatic bromination

A

substituting hydrogen with bromine

69
Q

aromatic nitration

A

benzene ring is attacked by the NO2+

70
Q

aromatic sulfonation

A

substituting a hydrogen atom in the benzene ring for the sulfonic acid group (attacked by SO3) SO3H is added to benzene

71
Q

aromatic alkylation

A

alkylbenzenes can be formed by reacting benzene with a haloalkane using an aluminium chloride catalyst

72
Q

ketones are reduced to

A

secondary alcohols

73
Q

electrophilic substitution involves

A

a benzene ring/ aromatic structure

74
Q

alkoxides

A

powerful nucleophiles and bases e.g. C2H5O-Na+

75
Q

making alkoxides

A

reacting an alkali metal e.g. Na with a dry sample of alcohol

76
Q

reacting a monohaloalkane witn NaCN in ethanol…

A

produces a nitrile and increases the carbon chain by 1

77
Q

nitriles can be converted to

A

carboxylic acids by acid hydrolysis using H+ ions as the catalyst (nucleophilic substitution reaction)

78
Q

dehydration of alcohols catalyst

A

concentrated sulfuric acid (H2SO4)

79
Q

base induced elimination

A

alkenes being produced from monohaloalkanes by heating with NaOH in ethanol

80
Q

dehydration of alcohols produces

A

alkenes using conc H2SO4

81
Q

oxidising agent

A

acidified dichromate

82
Q

acid chloride

A

a carboxylic acid with the -OH replaced with chlorine

83
Q

why is it more useful to react alcohols with acid chlorides than carboxylic acids

A

it is faster and does not require a catalyst

84
Q

amides

A

molecules with a CONH2 group

85
Q

phenyl group

A

when a hydrogen in a benzene ring is replaced by another group

86
Q

catalyst for electrophilic substitution of a chlorine atom on benzene

A

AlCl3 (if with Br for example it would be AlBr3)

87
Q

nitronium ion can be made by

A

mixing conc H2SO4 and conc HNO3

88
Q

catalysts of alkylation of benzene

A

AlCl3

adv higher chemistry (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions