Alkenes And Alcohols

Question 1

What type of mechanism do alkenes undergo

Answer 1

Electrophilic

Question 2

What happens in an electrophilic addition reaction

Answer 2

C=C attacks electrophile
Electrophile bond breaks
c=c breaks
Half electrophile on one C
C+ formed
Other half of electrophile attacks c+

Question 3

What is an electrophile

Answer 3

Electron pair acceptor

Question 4

Ethene + water –>

Concentrated sulfuric acid catalyst

Answer 4

Alcohol

Question 5

Test for alkenes

Answer 5

Shake alkene in bromine water

Orange to colourless

Question 6

Alkene + hydrogen halide –>

Answer 6

Halogenoalkane

Question 7

Primary carbocation structure

Answer 7

H
|
R-C-H
+

Question 8

Secondary carbocation structure

Answer 8

R
|
R-C-H
+

Question 9

Tertiary carbocation structure

Answer 9

R
|
R-C-R
+

Question 10

Why are tertiary carbocations more stable than primary carbocations

Answer 10

Carbocations with more alkyl groups are more stable because the alkyl groups feed electrons towards the positive charge

Question 11

What is a substituted alkene

Answer 11

Alkene that’s had a H atom substituted for another atom or group

Question 12

Dehydration of alcohols mechanism

Answer 12

Lone pair of electrons on the oxygen of the OH group on the alcohol attacks the H+ from the H2SO4 catalyst
The positively charged oxygen pulls electrons away from the carbon. Arrow from C-O goes to O+
H2O molecule leaves creating an unstable carbocation
Arrow goes from H-C to C-C
H is removed and C=C formed