Chapter 20, Problem 35A

Interpretation Introduction

Interpretation:

The prefixes ortho-, meta- and para- used in a disubstituted benzene are to be explained.

Concept introduction:

In a disubstituted benzene, prefixes ortho-, meta-, para - are used to tell the relative location of substituents.

Answer to Problem 35A

Ortho refers to 1,2-disubstituted benzene.

Meta refers to 1,3- disubstituted benzene.

Para refers to 1,4- disubstituted benzene.

Explanation of Solution

Two groups on benzene present relatively at 1,2 position are ortho to each other, 1,3 are meta to each other and 1,4 are at para position.

Ortho- dichlorobenzene is:

  

Meta-dichlorobenzene is:

  

Para-dichlorobenzene is:

  

Conclusion

Thus, ortho, meta and para tells about the relative position of substituents in disubstituted benzene ring.