Haloalkanes

Question 1

what is a secondary haloalkane?
draw an example

Answer 1

Two carbons attached to the
carbon atom adjoining the
halogen

Question 2

what is a primary haloalkane?

Answer 2

One carbon attached to the
carbon atom adjoining the
halogen

Question 3

what is a tertiary haloalkane?
draw an example

Answer 3

Three carbons attached to the carbon atom adjoining the halogen

Question 4

what is a nucleophile?

Answer 4

electron pair donor

Question 5

give 3 examples of nucleophiles

Answer 5

:OH-, CN:-, :NH3

Question 6

what mechanism do haloalkanes undergo?

Answer 6

nucleophillic substitution

Question 7

The rate of these substitution reactions depends on the strength
of the ____ bond
The ____ the bond, the ____ it is to break and the faster the reaction.

Answer 7

C-X , weaker, easier

Question 8

draw the template for a nucleophillic substitution recation

Question 9

The ____ are the fastest to substitute and the
_____ are the slowest. The strength of the C-F bond is
such that fluoroalkanes are very ____

Answer 9

iodoalkanes, fluroalkanes

Question 10

draw tetrachloromethane

Answer 10

Question 11

draw 1,1-dichloroethene

Answer 11

Question 12

draw 1,2-dibromo-2-methylbutane

Answer 12

Question 13

draw 1,2-dibromocyclohexane

Answer 13

Question 14

name CH3CH2CH2I

Answer 14

1-iodopropane

Question 15

name

Answer 15

2,3-dibromobutane

Question 16

name

Answer 16

1-fluoro-2-methylpent-2-ene

Question 17

write an equation for nucleophilic substitution with aqueous hydroxide ions of 1-bromopropane

Answer 17

In aqueous solution; Heat under reflux

Question 18

draw the mechanism for nucleophilic substitution with aqueous hydroxide ions of 1-bromoethane

Answer 18

Question 19

define hydrolysis

Answer 19

Hydrolysis is defined as the splitting of a molecule ( in this case a haloalkane) by a reaction with water

Question 20

Water is a ____ nucleophile but it can react slowly with haloalkanes in a substitution reaction. Use ____ OR heat
for more than ____ minutes

Answer 20

poor, reflux , 20

Question 21

in hydrolysis reactions, The ____ the precipitate is formed, the ____ the substitution reaction and the ____ reactive the haloalkane

Answer 21

quicker, faster , more

Question 22

what colour precipitates do the silver halides form?

Answer 22

Question 23

Aqueous ____ is added to a haloalkane and the
halide leaving group combines with a ____ ion to form a
____ precipitate.

Answer 23

silver nitrate, silver , silver halide

Question 24

CFC’s were developed for use as aerosols, refrigerants, and in air-conditioning due their low
____, ____ and non-____

Answer 24

reactivity, volatility, toxicity

Question 25

write the equation for ozone being broken down and reformed

Answer 25

Question 26

how is ozone formed?

Answer 26

UV light causes an O2 molecule to split into free radicals O2 + UV-light --> O + O When the free radical hits another O2 molecule ozone forms O + O2 --> O3

Question 27

what other radicals are responsible for ozone depletion?

Answer 27

nitrogen oxide radicals

Question 28

name 2 alternatives to CFCs

Answer 28

HCFCs + HFCs hydrocarbons

Question 29

The chlorine free radical atoms ____ the decomposition of ozone due to these reactions because they are regenerated. give the equations

Answer 29

catalyse

Question 30

why do CFCs still concern us?

Answer 30

CFCs are still entering the atmosphere from disused items and are still used for some purposes and by some countries. CFCs have a long lifetime in the atmosphere and it takes a long time for CFCs to reach upper atmosphere.