Benzene Flashcards

1
Q

What is benzene ?

A

An aromatic compound and a cyclic compound containing three conjugated double bonds
A ring of six sp2 hybrid carbon atoms each bonded to one hydrogen atom

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

What is the value of carbon-carbon bond length and bond angle

A

1.397A
Angle -120

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

Compare the bond length of benzene, single-bond and double-bond

A

Carbon-carbon bond length in benzene is shorter that single-bound length, yet longer than typical double-bond length

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

What happens when bromine is added to benzene ?

A

No reaction occurs and the red bromine color remains

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

What reaction does benzene undergo substitution or addition?

A

Substitution

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

What is the only cyclic compound that shows resonance ?

A

Benzene

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

Define annulenes

A

Cyclic hydrocarbons with alternating single and double bonds

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

What type of bonds are present in benzene ?

A

3 sigma bonds

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

How are the hybrid orbitals arranged in benzene ?

A

In a trigonal planar geometry

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

How many pi electrons does benzene have ?

A

6

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

What are the type of molecular orbitals that the benzene has?

A

Three bonding orbitals → contribute to stability
Three anti-bonding orbitals → higher in energy and electrons are not paired

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

What is the Huckel’s rule ?

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

What is the adverse effect of benzene?

A

Causes leukemia → decrease of RBC and increase in malfunctioning WBC
Metabolites of benzene may react with proteins and DNA in the bone marrow alerting the production of red and white blood cells

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

Can people and animals make benzene nucleus ?

A

No, however it is a key component of the essential amino acid phenylalanine, so they must obtain phenylalanine in their diet

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

How do plants and bacteria get phenylalanine?

A

They can synthesize the aromatic ring and their own phenylalanine

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

Benzene derivatives have been isolated and used as what ?

A

Industrial reagents

17
Q

Disubstituted benzenes are named using what prefixes ?(common name)

A

Ortho
Meta
Para

18
Q

When is benzene called phenyl?

A

When the benzene ring is a substituent on another molecule

19
Q

What is a benzoyl group ?

A

The seven-carbon unit consisting of a benzene ring and a methylene group