When the three dibromobenzenes are mononitrated, the one melting at `87^@C` gives only one mononitro product, while those with melting points of `6^@C` and `-7^@C` give two and three mononitro derivatives, respectively. Which of the following statements is correct?

Options

A. The isomer melting at `87^@C` is para-dibromobenzne.
B. The isomer meting at `6^@C` is ortho-dibromobenzene.
C. The isomer meting at `-7^@C`
D. None of these

Answer

D

Explanation

These results led korner in 1875 to assign structures to the three isomeric dibromides. The only dibromide with four equivalent position for mononitration is para the dibromide with two equivalent position is ortho while the dibromide with three identical position is meta.