Aromatics

Question 1

Why would hydrogen bromide react quicker than hydrogen chloride in a mechanism

Answer 1

The hydrogen bromide bond has a lower enthalpy so it requires less energy to break so its quicker

Question 2

What did Michael faraday do

Answer 2

First isolated benzene

Question 3

What did michael faraday do alongside separating benzene

Answer 3

He discovered that the empirical formula was a 1-1 carbon to hydrogen ratio

Question 4

What did Kekule claim

Answer 4

That benzene consisted of a cyclic hexene ring with three alternating double bonds

Question 5

What are two faults in kekules benzene model

Answer 5

With the three double bonds it would undergo electrophillic addition and produce two isomeric compounds
Single and double bonds are different lengths so it wouldn’t be symetrical

Question 6

What did theorists come up with to support kekules benzene model and the symmetry

Answer 6

That the three double bonds were alternating creating the illusion of symmetry

Question 7

Who proves kekules benzene model incorrect and how

Answer 7

Kathleen londsdale who proved that benzene has a hexagonal structure with bonds of equal lengths

Question 8

How did Kathleen prove kekules benzene model incorrect (with what equipment)

Answer 8

An X-ray

Question 9

The latest benzene structure

Answer 9

By Kathleen
It is planar regular hexagonal ring with sae lengths

Question 10

What are the lengths of Kathleen’s benzene model

Answer 10

An intermediate length of a single and double bond

Question 11

Is benzene usually stable or unstable

Answer 11

Unstable

Question 12

What is benzene being unstable also known as

Answer 12

Aromatic stability

Question 13

Ho are electrons arranged in benzene

Answer 13

They are delocalised across all six carbons in a conjugated system with overlapping electron clouds

Question 14

What is the chemical formula of benzene

Answer 14

C6 H6

Question 15

How many bonds does carbon have in benzene and what does that do

Answer 15

Carbon has three bonds so the fourth electron is delocalised inn the conjugated system of overlapping P-orbitals

Question 16

What does the enthalpy during hydrogenation prove

Answer 16

That the theoretical isnt correct since the enthalpy is higher than in reality

Question 17

What does being less exothermic mean fo a element

Answer 17

That it is more stable