Question

Ethyl group $(-C{H}_{2}C{H}_3)$ in ethylbenzene increases electron density at which of the following positions?

• A. Ortho-Meta .
• B. Ortho-Para .
• C. Meta only.
• D. Ortho, Meta and Para.

Answer 1

The correct option is B Ortho-Para .

In general, hyperconjugation effect is more dominating as compared to inductive effect, and due to hyperconjugation in ethyl benzene the electron density increases at ortho and para positions as shown :
In structure II , III and IV we can see that negative charge is delocalized at ortho and para position, so it increases the electron density at these positions .