Lecture 10

Question 1

Free radicals

Answer 1

Atoms or group of atoms with unpaired electrons, reactive but not unstable

Question 2

What are the 3 major steps in a radical reaction

Answer 2

1) initiation –> creates radical. Need UV to break bond

2) Chain Propagation –> Radicals generate more radicals

3) Chain termination –> 2 radicals react to form non-radicals

Question 3

Reaction to make Hydroxyl Radical

Answer 3

one of the most important tropospheric sinks

NO2 + hv –> NO+O
O + O2 + M –> O3 + M + KE
O3 + hv –> O2* + O*
O* + H2O –> 2.OH

Question 4

Reaction to make Hydroperoxyl radical

Answer 4

HCHO + hv –> .H + HCO.
or
HCO. + O2 –> HOO. + CO

Question 5

methyl radical (CH3.)

Answer 5

OH + CH4 –> .CH3 + H2O

Question 6

Finding ΔHrxn (kj/mol)

Answer 6

ΣD(bonds broken) - ΣD(bonds formed)