Halogenoalkanes

Question 1

Explain why halogenoalkanes have polar bonds

Answer 1

Halogens have a higher electronegativity than carbon

Question 2

What forces do they have?

Answer 2

Permanent dipole-dipole
Van der Waals

Question 3

Explain the order of reactivity of halogenoalkanes?

Answer 3

Bond enthalpy decreases down the group
Therefore reactivity increases down the group

Question 4

What is a nucleophile?

Answer 4

A negatively charged ion that can donate a lone pair of electrons to an electron deficient atom

Question 5

What are 3 examples of a nucleophile?

Answer 5

:OH-
:CN-
:NH3

Question 6

What is nucleophilic substitution?

Answer 6

Nucleophile donates a lone pair of electrons to a S+ C atom, which replaces the H originally attached to the carbon

Question 7

What are the problems with CFCs?

Answer 7

They catalyse the breakdown of ozone in the atmosphere
Via free radical substitution

Question 8

What are the conditions / reagents required for an elimination reaction?

Answer 8

NaOH or KOH dissolved in ethanol
Heated