Question

1.Direct substitution of an existing group can be done by (choose all that apply)?

Multiple answers: You can select more than one option

A.using a diazonium

B.doing an ipso substitution

C.treating benzene with a nucleophile

D.treating halobenzene with a base

E.catalytic hydrogenation

Answer 1

A.using a diazonium

B.doing an ipso substitution

explanation :

in diazonium salts N2+ group is directly replaced by other groups . so this is direct substitution

suppose :   benzene diazonium salt react with KI , N2 is replaced by I

C6H5N2+Cl-    + KI -----------------------------> C6H5I + N2 + KCl

ipso substitution

it is the substitution at first position in the benzene ring this can also be done direct sub

C)

benzene cannot participate in nucleophile reactions

D)

treating halobenzene with a base cannot be happed directly

E)

catalytic hydrogenation this is addition reaction so it cannot be answer