Answer:
See explanation
Explanation:
For this question, we have to remember the definition of a meso-compound. In a meso-compound, we will have chiral carbons but we don't optical activity. This is due to the symmetry, if we have symmetry in a substance with chiral carbons the optical activity is nullified. So, if we want to find the meso-compounds we have to find symmetry planes in the molecule.
A symmetry plane is an imaginary cut that can divide the molecule in two equal parts. We have to draw the molecule first (see figure 1) and then we can try to find the symmetry planes.
With this in mind, the only compounds with symmetry planes are:
b) cis-1,3-dimethylcyclohexane
d) cis-1,4-dimethylcyclohexane
See figure 2 to more explanations
I hope it helps!
