Demonstration of nitrobenzene


Chemicals needed

benzene  GSGiftig.gif (734 Byte) T  GSLEICHT.gif (932 Byte) F    R 45-11-48/23/24/25      S 53-45

nitric acid 65% GSATZEND.gif (935 Byte) C    R 35     S(1/2)-23-26-27

Sulphuric acid 96%  GSATZEND.gif (935 Byte) C    R 35   S (1/2)-26-30-45


Dangerous substance information

nitrating acid GSBRANDF.gif (891 Byte) O GSATZEND.gif (935 Byte) C    R 8-35     S (2)-23-26-30-36-45

nitrobenzene GSGiftig.gif (734 Byte) T GSUMWELT.gif (758 Byte)  N    R 23/24/25-40-48/23/24-51/53-62    S (1/2)-28-36/37-45-61


Equipment needed

test tube
beaker
pear shaped flask or the like


Test procedure


Disposal


Elucidation

Benzene is only moderately activated with respect to electrophilic substitution. Therefore concentrated sulphuric acid must be added for the insertion of the nitric acid nitro group. As nitrobenzene is still less activated, under these conditions only one nitro group is inserted into the benzene nucleus.


Photos

DSCN0460.JPG (244126 Byte)

The reaction mixture shortly after the addition of benzene.

DSCN0462.JPG (231446 Byte)

The reaction mixture towards the end of the reaction.

DSCN0464.JPG (196923 Byte)

Nitrobenzene is heavier than the highly diluted nitrating acid and settles.


Literature

cf. experiment 1951S, "Bildung von Nitrobenzol", p. 329, [2]