Brainscape's Knowledge GenomeTM

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


See full index

Advanced higher chemistry > Molecular orbitals and stereochemistry - organic > Flashcards

Molecular orbitals and stereochemistry - organic Flashcards

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

How are molecular orbitals formed

A

By atomic orbitals overlapping

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

What happens when two atomic orbitals combine

A

An anti bonding and bonding molecular orbital form.

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

How many electrons are in a molecular orbital

A

2

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

What happens when there is an end on overlap of atomic orbitals

A

A sigma bond is formed.

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

What happens when there is a side on overlap of atomic orbitals

A

A pi bond is formed

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

What happens when non polar covalent atomic orbitals overlap

A

The molecular orbital will be symmetrical around the mid point of the orbital.

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

What happens when polar covalent atomic orbitals overlap

A

The molecular orbital will be asymmetrical around the mid point of the orbital.

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

Rule of hybridisation

A

When different atomic orbitals a set of degenerate hybrid orbitals are formed.

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

Types of carbon hybridisation

A

sp3, sp2, sp

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

Sp3 hybridisation
Orbital structure

A

Where carbon goes from 1s2, 2s2, 2p2
To 1s2, sp3

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

sp3 molecular structure

A

Tetrahedral structure

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

Type of bond in sp3 hybridisation

A

Carbon single bonds

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

Sp2 hybridisation orbital structure

A

1s2, 2s2, 2p2
To 1s2, sp2 2p1

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

sp2 molecular structure

A

Trigonal planar

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

Type of bond in sp2

A

Carbon double bond

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

Types of orbital bond in sp3

A

7 sigma bonds

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

Types of orbital bond in sp2

A

5 sigma bonds and 1 pi bond

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

sp orbital structure

A

1s2, 2s2, 2p2
To 1s2 sp 2p2

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

Type of bond in sp hybridisation

A

Carbon triple bond

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

Types of orbital bonds in sp hybridisation

A

3 sigma + 2 pi

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

sp molecular structure

A

Linear

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

Alkynes homologous series

A

A group of hydrocarbons with a carbon to carbon triple bond

23
Q

Alkynes general formula

A

CnH2n-2

24
Q

What is a skeletal structure

A

Where in organic chemistry we draw compounds without carbons and assume there is the maximum number of hydrogens bonded on.

25
Q

What does a benzene ring look like

A

It’s a hexagon with three lines inside for double bonds.
Or a hexagon with a circle inside it.

26
Q

What does LUMO stand for

A

Lowest unoccupied molecular orbital

26
Q

What type of molecular orbital is a LUMO

A

Anti bonding

27
Q

What does HOMO stand for

A

Highest occupied molecular orbital

28
Q

What type of molecular orbital is HOMO

A

Bonding molecular orbital

29
Q

What type of light is absorbed by molecular orbitals without conjugated systems

A

UV light because the energy gap between the orbitals is so high

30
Q

What is a conjugated system

A

Where an organic substance has a chain of repeating carbon single and double bonds, creating delocalised electrons across many different atoms bonding molecular orbital.

31
Q

Conjugated system structure

A

Alternating carbon single and double bonds.

32
Q

Rule of energy gap and conjugated system

A

The larger the number of atoms in the conjugated system the lower the energy gap between the HOMO and LUMO

33
Q

Why are some organic substances coloured

A

Because they have long conjugated system which means that there is a lower energy gap between the HOMO and LUMO which means some wavelengths of light will be absorbed to promote electrons to higher energy levels, the complimentary colour will then be shown by the substance as this is the wavelengths of light reflected.

34
Q

What is a chromophore

A

A group of atoms within a molecule responsible for absorbing visible light

35
Q

Rule of chromophore and colour of compound

A

The compound will absorb the wavelengths of light which promote electrons to higher energy levels and all over wavelengths of light will be reflected, which shows the colour of the compound.

36
Q

How do indicators work

A

The indicator goes from deionised to ionised which forms a large conjugated system and makes the indicator change colour.

37
Q

Example of indicator

A

Phenolphthalein

38
Q

Stereoisomers definition

A

Where a molecule has the same molecular and structural formula but different 3D arrangement in space.

39
Q

Geometric isomers examples

A

Carbon to carbon double bonds and cyclo ring structure molecules.

40
Q

Cis

A

When the two groups are on the same side.

41
Q

Trans

A

Where the two groups are on different sides.

42
Q

Rules of geometric isomerism

A

For geometric isomerism to occur there must be two different groups attached to the carbon atoms that make up the bond with restricted rotation.

43
Q

How do geometric isomers differ

A

Influences chemical properties
Influences physical differences

44
Q

Chemical properties example

A

Undergoes condensation or not

45
Q

Physical differences

A

Difference in mp/ bp

46
Q

Geometric isomers definition

A

Stereoisomers which have two different groups attached to carbon atoms that make up a bond with restricted rotation.

47
Q

Optical isomers

A

Stereoisomers which are non super imposable mirror images of each other.

48
Q

Enantiomers

A

Optical isomers (interchangeable)

49
Q

Chiral centre

A

A carbon atom in an optical isomers where there are four different groups attached.

50
Q

Enantiomers properties

A

In chiral environments they have different physical and chemical properties
In normal environments they have the same properties.

51
Q

How to distinguish Enantiomers

A

They rotate polarised light in an equal and opposite way.

52
Q

What is optically active

A

When Enantiomers rotate polarised light in an equal and opposite way.

53
Q

Racemic mixture

A

Enantiomers of equal proportions which aren’t optically active.

Advanced higher chemistry (8 decks)

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