Brainscape's Knowledge GenomeTM

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


See full index

Semester 2 Chemistry Revisions > Lecture 8 > Flashcards

Lecture 8 Flashcards

1
Q

What is the bonding in alkenes?

A

Two sp2 orbitals overlap to form a sigma bond between two carbon atoms.
Two 2p orbitals overlap to form a pi bond between the two carbon atoms.
S orbitals in hydrogen overlap with the sp2 orbitals in carbon to form CH bonds.

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

Due to the bonding in alkenes what is the resulting shape of an alkene?

A

Planar

Bond angle- 120o.

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

What is the IUPAC suffix for an alkene?

A

“ene”

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

What is the older nomenclature suffix for an alkene?

A

“ylene”

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

What is geometric isomerism and example of?

A

STEROISOMERISM

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

What causes geometric isomerism?

A

Occurs due to the RESTRICTED ROTATION around the Carbon- Carbon double bond.

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

When is it E isomerism?

A

Higher ranked substituents on OPPOSITE sides.

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

When is it Z isomerism?

A

Higher ranked substituents on SAME side.

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

In the elimination of HX from haloalkanes, what happens?

A

There is a loss of H+ and X- ions from ADJACENT carbons, forming a new pi bond.

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

What is the reagent and reaction conditions for the haloalkane to alkene (elimination)?

A

REAGENT: Alcoholic KOH/ NaOH
CONDITIONS: Reflux in alcoholic solution.

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

What is the reagents for dehalogenation of vicinal dibromides?
What type of reaction is this?

A

REAGENTS: NaI and Zn/HOAc- Redox Reaction.

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

What happens in the reaction of dehydration of alcohols?

A

Removal of Water.

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

What is the reagent and reaction conditions for the dehydration of alcohol?

A

REAGENT: Catalytic acid- Eg. Sulfuric or Phosphoric acid.
CONDITIONS: Reflux (Depends on alcohol).

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

What side reaction might occur alongside the dehydration of alcohols?

A

Rearrangement Reaction

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

In the Krebs Cycle what reaction occurs between citric acid to ascontic acid?

A

Elimination of water.

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

In the Krebs cycle what happens to Succinic Acid to produce fumaric acid? What reaction is it?

A

Hydrogen is removed.

Dehydrogenation reaction.

17
Q

Physical Properties: Boiling Point

A

INCREASES up the homologous series because of Van der Waals’ forces.
Trends similar to those in ALKANES.

18
Q

Physical Properties: Melting Point

A

Increases up the homologous series, but depends on the isomer, for example see fatty acids.

19
Q

Physical Properties: Solubility

A

Immiscible (don’t mix with) with WATER or some POLAR solvents.
MISCIBLE with/soluble in most organic solvents.

20
Q

Physical Properties: Density

A

LESS dense than water.

21
Q

Why are pi bonds weaker than sigma bonds in alkenes?

A

Pi electrons are FURTHER from the carbon nuclei and so are less firmly bound.

22
Q

What is the reagent for the addition reaction of Hydration (H2O)?

A

H2O- Acid Catalyst

23
Q

What is the reagent for the creation of an bromine haloalkane?

A

Eg. Br2.

24
Q

What is the reagent for the addition reaction of halohydrin formation?

A

Br2 in water.

25
Q

What is the reagent for the hydrogenation (Chemical Reduction)?

A

H2 and transition metal catalyst.

26
Q

Markovnikov’s Rule: Which carbon does the hydrogen atom add to?

A

The Carbon with the Greater number of hydrogen atoms.

27
Q

Markovnikov’s Rule: Why does the most stable carbocation form?

A

Alkyl groups are ELECTRON RELEASING and can “push” electrons towards the CARBOCATIONS which STABILISES them. The more alkyl groups the most electrons can be pushed towards the carbon.

28
Q

What is the major formed via?

A

The most stable carbocation.

29
Q

In biological reduction what happens during this reaction?

A

One end of the double bond has a H- transferred and the other end transfers a H+.
Cofactor- H-
Amino acid residue- H+

30
Q

Why does chemical reduction of alkenes require a transition catalyst?

A

The catalyst associates on the surface of the hydrogen- weakens the H-H bond.
In reduction the transition metal causes the electron density to be taken out of H (partial bond to transition metal) so H more likely to react.

31
Q

What is epoxidation?

A

The addition of an OXYGEN atom in a 3 membered ring. CP450 will add the oxygen effectively.

32
Q

What is dihydroxylation?

A

2 OH groups are added to either end. (hydroxylation= HOOH)

Dihydroxylation detoxification are products of epoxidation.

33
Q

What is oxidation cleavage?

A

CORRECT oxidising agent can split the ALKENE into 2 CARBONYL groups.

34
Q

What are the reagents for diyhdroxylation reaction? Why?

A

OsO4 (Osmium Tetroxide) or cold alkaline KMnO4.

Transition Metal Catalyse to oxidise alkenes by the oxygen atom bonding to the metal which is transferred to the alkene.

35
Q

In the initiation step what is turned into a radial?

A

The Organic Peroxide.

36
Q

What are the requirements for radical polymerisation?

A

High Pressure
High Temperature
Catalyst

37
Q

Why is a catalyst needed in radical polymerisation?

A

Readily breaks up to form radicals which initiate a chain reaction.

Semester 2 Chemistry Revisions (12 decks)

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