The atmosphere

Question 1

heterolytic fission and homolytic??

Answer 1

homo = O. + O. 
heter = O.. + O (ions)

Question 2

radicals chain reactions and radiation. 3 steps?

Answer 2

initiation = starting it 
propagation = making it continue 
termination = ending it

Question 3

eg of chain reaction with H2 and Cl2

Answer 3

1.Cl-Cl –> Cl. Cl.
2.Cl. + H-H –> Cl - H + H.
H. + Cl - Cl –> H-Cl + Cl.
3. H. + Cl. –> H-Cl
H. + H. –> H-H
Cl. +Cl. –> Cl-Cl

Question 4

little radiation and matter =

Answer 4

bump translational energy

iie radiowaves

Question 5

increased energy and matter 2?

Answer 5

rotate & move rotational energy ir microwave

Question 6

more enery and matter 3

Answer 6

vibrational energy, vibrate ir infrared

Question 7

even more energy 4 (LAST)

Answer 7

electrons excite to hugher energy levels and then return to orginial state
ie. uv and visible ‘electronic’

Question 8

ozone facts

Answer 8

O3; v. oxidising, pollutant, bad to cells, vital in stratosphere to filter out UV

Question 9

steady equilibrium of ozone in atmosphere?

Answer 9

2O3 == 3O2

Question 10

danger in troposphere

Answer 10

O + O2 –> O3

Question 11

O2 + hv –> ?

Answer 11

O + O

UV makes O

Question 12

Ozone cycle

Answer 12

–>O2–HV–> O + O —> O + O2 —> O+ O3——————————
|-hv—

Question 13

hydroxyl radicals

Answer 13

H2O + O. –> 2OH
OH + O3 –> HO2 +O2
HO2 + O –> OH + O2

Question 14

CFCs stands for?

Answer 14

chlorofluorocarbons

Question 15

CFCs and ozone depletion=

Answer 15

bonds break between non CFC elements. ie C-Cl bond = C + Cl.
Cl. go onto depletion

Question 16

manmade ozone depletion

Answer 16

CF3-Cl -hv-> CF3. + Cl. 
(Cl) + O3 ---> ClO + O2 
ClO + O --> (Cl) + O2 
O + O3 --> O2 + O2 
Cl + O3 --> ClO + O2 
Both remove O3. Cl radical is in low concentration but activation energy is low for this reaction so it proceeds rapidly

Question 17

Greenhouse gases examples

Answer 17

CFCs 
N2O
H2O
Methane -- cows and rice farming 
CO2-- burning fossil fuels

Question 18

What is a greenhouse gas?

Answer 18

Gas that absorbs infrared trapping heat

energy from the sun not absorbed by the atmosphere

Question 19

Dissociation?

Answer 19

covalent bond undergoes homolytic fission –> 2 radicals ands because of UV