Alkenes

Question 1

Stability of carbocation justifying template:

Answer 1

• classify the carbocations the products are formed from
• compare relative stability of these carbocation intermediates
• justify relative stability of carbocations

Question 2

Justify why 2-bromopropane is the major product of such reaction: (3)

Answer 2

• 2-bromopropane is formed via a secondary carbocation whereas 1-bromopropane is made via primary carbocation
• secondary carbocation more stable than primary carbocation
• because it has a larger positive inductive effect/more electron releasing alkyl groups

Question 3

conditions needed for industrial preparation of ethanol:

Answer 3

• steam
• high pressure (70 atm)
• high temperature (300 to 600)
• concentrated H3PO4 catalyst

Question 4

Name product made from alkene + sulfuric acid
* name reagent
* mechanism

Answer 4

alkylhydrogensulfate
* H2SO4
* electrophilic addition

Question 5

Why sulphur dioxide may be found in the exhaust gases of cars (1)

Answer 5

hydrocarbon mixture has sulphur-containing impurities