AS.14 Haloalkanes

Question 1

C-X bond enthalpy

Answer 1

Larger enthalpy = stronger bond

Down group - bond enthalpy decrease

Question 2

Hydrolysis

Answer 2

Addition of water to break a bond

Question 3

Measuring bond enthalpy of C-X bond

Answer 3

Add AgNO3 and H2O with ethanol and measure time taken for precipitate to form

CH3Cl + H20 ——-> CH3OH + H+ + Cl-

Ag+ + Cl- ———> AgCl (s)

Rate of hydrolysis ——-> faster = weaker bond

Question 4

Nucleophile

Answer 4

Electron pair donor

Question 5

CFCs

Answer 5

Danger to environment because of free radicals they can form that degrade ozone layer

            U.V. CF3Cl —————-> CF3* + Cl*

Question 6

Ozone layer

Answer 6

U.V
O2 + O <————> O3

Question 7

Photodissociation

Answer 7

Breaking bonds with U.V.

Question 8

Ozone layer - NO2

Question 9

Why still concern about ozone depletion

Answer 9

CFC still used

CFC take many years to reach ozone layer