Explain why although alkyl halides are slightly polar, they are insoluble in water.

Explain why for a given alkyl group, the order of boiling point is:

$\mathrm{RI}>\mathrm{RBr}>\mathrm{RCl}>\mathrm{RF}$

Explain why for a given alkyl group, the order of reactivity is:

$\mathrm{RI}>\mathrm{RBr}>\mathrm{RCl}>\mathrm{RF}$