ALKENES

Question 1

unsaturated, double bonded hydrocarbon

Answer 1

Alkene

Question 2

contains carbon-carbon double bonds

Answer 2

Alkenes

Question 3

do not contain the maximum number of hydrogen atoms.

Answer 3

Unsaturated hydrocarbons

Question 4

They react with hydrogen gas to
increase the number of hydrogen
atoms to become alkanes

Answer 4

saturated hydrocarbons

Question 5

General formula

Answer 5

CnH2n (for one double bond)

Question 6

molecule is ____ and ___ because the carbon and hydrogen atoms all lie in the same plane

Answer 6

Flat and planar

Question 7

result from combinations of orbitals within a given atom,
either prior to or as bonding with another atom takes place.

Answer 7

Hybrid Orbitals

Question 8

result from combinations of orbitals between atoms as bonding takes place to form
molecules

Answer 8

Molecular orbitals

Question 9

produce three sp^2 orbitals

Answer 9

combining the 2s and two of the 2p orbitals

Question 10

a noncyclic hydrocarbon substituent in which a C-C double bond is present

Answer 10

Alkenyl group

Question 11

Most Frequently encountered alkenyl groups

Answer 11

Methylidene (one- carbon)- Common name:
methylene

Question 11

Most Frequently encountered alkenyl groups

Answer 11

Methylidene (one- carbon)- Common name:
methylene

Question 12

an exception because it is a
colourless gas with a faintly sweet odour

Answer 12

Ethene

Question 13

the first three members of the alkene group

Answer 13

gaseous in nature

Question 14

the next fourteen
members

Answer 14

are liquids and the remaining
alkenes are solids

Question 15

______ in water
due to their nonpolar characteristics

Answer 15

Insoluble

Question 16

Completely ____ in nonpolar
solvents such as benzene, ligroin

Answer 16

soluble

Question 17

The boiling points of the compounds ______ as
the number of carbon atoms in the compound
increases

Answer 17

increase

Question 18

Have a lower melting point than trans- isomers as the molecules are packed in a U-bending shape

Answer 18

cis-isomer molecule

Question 19

Alkenes are weakly polar just like alkanes but
are slightly more reactive than alkanes due to

Answer 19

presence of double bonds

Question 20

produced naturally by all higher plants from the amino acid methionine and is a plant growth
regulator. It causes trees to lose their leaves
and stems to thicken.

Answer 20

ethene

Question 21

compound used by insects
(and some animals) to transmit a message
to other members of the same species

Answer 21

Pheromone

Question 22

organic compound whose carbon skeleton is composed of two or more 5-carbon isoprene structural units

Answer 22

Terpenes

Question 23

produced primarily as a by-product of petroleum refining and of ethylene production by steam cracking of hydrocarbon feedstocks

Answer 23

propylene

Question 24

the orange pigment that gives
carrots their color. It is an important dietary
source of vitamin A and is thought to offer
some protection against certain types of
cancer.

Answer 24

B-Carotene

Question 25

an organic compound of the
terpene class. It is found in the oils of many
species of many coniferous trees, notably
the pine

Answer 25

a-pinene

Question 26

Alkenes are generally prepared through Alkenes are generally prepared through _____ , in which
two atoms on adjacent carbon atoms are removed, resulting in the
formation of a double bond.

Answer 26

β elimination

Question 27

Alkenes can be prepared using the following methods

Answer 27

a. Dehydration of alcohols
b. Dehydrohalogenation of alkyl halides
c. Dehalogenation of alkanes

Question 28

In ________, a molecule of water is eliminated from an
alcohol molecule by heating the alcohol in the presence of a strong
mineral acid

Answer 28

dehydration reactions