Chapter 15

Question 1

What are haloalkanes?

Answer 1

Compounds containing hydrogen, carbon and a halogen

Question 2

What are nucleophiles?

Answer 2

Species that can donate a pair of electrons.

Question 3

Hydrolysis

Answer 3

Hydrolysis is a chemical reaction involving water or an aqueous solution of a hydroxide that causes the breaking of a bond in a molecule
The hydrolysis of an haloalkane results in the halogen atom being replaced by -OH group

Question 4

Rate of hydrolysis

Answer 4

The rate depends on the strength of the carbon halogen bond.
As you go down group 7, the halogen-carbon bond becomes weaker
This means iodoalkanes are very reactive and fluroalkanes are unreactive
Rate also depends on the type of haloalkane. Tertiary haloalkanes are more reative than primary and secondary

Question 5

What are Organohalogen compounds?

Answer 5

Molecules that contain at least one halogen atom joined to a carbon chain. Used for solvents, making polymers, refrigerants.

Question 6

What is the Ozone layer?

Answer 6

Layer which absorbs most of the uv radiation
Ozone is continously being formed and broken down
O2->2O
O2+O->O3

Question 7

How did CFCs affect the ozone layer?

Answer 7

Since CFCs were stable and unreactive, they are able to reach the stratosphere and then it breaks down to form chlorine radicals which catalyse the breakdown of the ozone layer.
CF2Cl2->CF2Cl”+CL’
The chlorine radical is very reactive and can break down the ozone layer to form oxygen.

Question 8

Natural causes of depletion of ozone layer

Answer 8

Nitrogen oxide formed naturally from lightning, form radicals and break down the ozone layer