Question

How can you prepare benzene from ethyne?
Arrange the following in decreasing order of reactivity toward electrophilie
substitution reaction
Chlorobenzene, 2.4-Dinitrochlorobenzene, 4-Nitrochlorobenzene​

Answer 1

Answer:

heating ethyne in iron tube with copper gives you benzene (I think)

Explanation:

decreasing order for electrophilic substitution

chlorobenzene>4 nitro chlorobenzene>2,4Dinitrochlorobenzene

see order of -m groups