How aryl halides react with sodium metal? Explain why alkyl halides show nucleophilic substitution reaction ?

Aryl halide are less reactive than alkyl halides towards nucleophilic substitution reactions. Why ?

Carbonyl compounds mainly show nucleophilic addition. reactions. Why?

Explain S_N^2 reactions. What is the preference order of different alkyl halides to undergo nucleophilic substitution reaction via SN2 mechanism ?

Allyl chloride is more reactive than n-propyl chloride towards nucleophilic substitution reaction. Explain why ?

Elimination reactions (especially beta -elimination) are as common as the nucleophilic substitution reaction in case of alkyl halides. Specify the reagents used in both cases.

Elimination reactions (especially beta -elimination) are as common as the nucleophilic substitution reaction in case of alkyl halides. Specify the reagents used in both cases.