module 4: alkenes

Question 1

functional group

Answer 1

C=C

Question 2

geometric isomer

Answer 2

same molecular and structural formula, different spatial arrangement of atoms

Question 3

E/Z isomerism condition

Answer 3

each carbon atom in C=C bond has two different functional groups attached

Question 4

pi bond

Answer 4

double bonds
sideways overlap of adjacent p orbitals above and below the plane
restricted rotation

Question 5

E

Answer 5

substituent groups on opposite sides of double bond

diagonal, Z shape

Question 6

Z

Answer 6

substituent groups on same side of double bond

Question 7

CIP

Answer 7

functional group on each carbon assigned a priority based on atomic number

note: if two atoms have same atomic number, the adjacent atoms with highest atomic number are taken into account

Question 8

cis/trans special case

Answer 8

both carbon atoms have the same functional groups

two of the substituent groups must be H

Question 9

preparation of alkenes via steam/ thermal cracking

Answer 9

high temperature and pressure
produces a high alkene yield

Question 10

preparation of alkenes via catalytic cracking

Answer 10

Al2O3 catalyst + pressure
heterogeneous
aromatic hydrocarbons produced