AS Chemistry A OCR - Haloalkanes

• A species that donates a pair of electrons.

• When added to water, OH- ions are formed.
• Examples are NH3 and NaOH

• The C-CL bond is polar.
• The OH- Ion gives an electron pair to the carbon, forming a dative covalent bond.
• The Cl atom takes the bonding electrons from the bond as it's more electronegative.

• Creates Ag+ ions when in solution.

• Ethanol and Water used because everything is soluble in this solution.

• The time taken for a precipitate of silver halide to appear will depend on how much of everything you use and the temperature at which the reaction is carried out. But the pattern of results is always the same.

A primary iodo compound produces a precipitate quite quickly.

A primary bromo compound takes longer to give a precipitate.

A primary chloro compound probably won't give any precipitate for many hours.

• C-F is the strongest bond at ~485KJ per Mol
• C-Cl is slightly weaker at ~330KJ per Mol
• C-Br is slightly more weaker at ~285 KJ per Mol
• C-I is even weaker at ~210 KJ Per Mol

• Unreactive
• Unflammable
• Nonetoxic

• When the CFC's reach the ozone layer, because of UV light, the C-Cl Bond breaks homolytically and creates two radicals.
• The Cl radical then reacts with an ozone molecule, creating ClO radical and O2.
• The ClO radical reacts with an oxygen atom, creating Cl radical and O2.