Chapter 15

Question 1

Substituents are listed

Answer 1

alphabetically

Question 2

Primary haloalkane

Answer 2

One carbon attached to the carbon atom adjoining the halogen

Question 3

Secondary haloalkane

Answer 3

2 carbons attached to the carbon atom adjoining the halogen

Question 4

Tertiary haloalkane

Answer 4

3 attached to the carbon atom adjoining the halogen

Question 5

Substitution:

Answer 5

swapping a halogen atom for another atom or groups of atoms

Question 6

Nucleophile:

Answer 6

electron pair donator e.g. :OH-, :NH3, CN-

Question 7

nucleophiles always have

Answer 7

a lone pair and act as
electron pair donators

Question 8

The rate of these substitution reactions depends on the strength
of the C-X bond
The weaker the bond,

Answer 8

the easier it is to break and the faster the reaction.

Question 9

Hydrolysis

Answer 9

splitting of a molecule ( in this
case a haloalkane) by a reaction with water

Question 10

AgI(s) -
AgBr(s)-
AgCl(s) –

Answer 10

AgI(s) - yellow precipate
AgBr(s) – cream precipitate
AgCl(s) – white precipitate

Question 11

order of silver halides- hydrolyses fastest to least

Answer 11

AgI
AgBr
AgCl

Question 12

CFC uses and why

Answer 12

-aerosols
-refrigerants
-air conditioning
BECAUSE low reactivity, volatility and non toxicity

Question 13

What is used now instead of CFCs and why

Answer 13

HFCS
used as refrigerants and ACS- no C-Cl bond

Question 14

ozone formation

Answer 14

UV light causes O2 to split into free radicals
O2-> O + O
THEN free radical hits another O2 molecule- ozone forms
O + O2 -> O

Question 15

Ozone depletion

Answer 15

The energy is supplied by ultraviolet light
O3 + ultraviolet light -> O2 + O

Question 16

The frequency of ultra-violet light absorbed =

Answer 16

the frequency of biologically damaging ultra-violet radiation.

Question 17

rate of ozone formation =

Answer 17

rate of ozone removal

Question 18

Chlorine radicals are formed in the upper
atmosphere when…
+ equation

Answer 18

energy from ultra-violet
radiation causes C–Cl bonds in (CFCs) to break
CF2Cl2->CF2Cl. + Cl.

Question 19

The chlorine free radical atoms catalyse the
decomposition of ozone due to these reactions
because they are regenerated.
EQUATION( two step and overall)

Answer 19

Cl. + O3 -> ClO. + O2
ClO. + O. -> O2 + Cl.
Overall equation
O3 + O. -> 2 O2

Question 20

nitric acid catalysing the decomposition of ozone
two step and overall

Answer 20

NO + O3 -> NO2 + O2
NO2 + O. -> O2 + NO
Overall equation
O3 + O. -> 2 O2