Question

In X- H ----- Y, X and Y both are electronegative elements

• A. Electro density on X will increase and on H will decrease
• B. In both electron density will increase
• C. In both electron density will decrease
• D. On X electron density will decrease and on H increases

Answer 1

Answer: (A)

Electro density on X will increase and on H will decrease

Answer 2

The correct option is(A): Electro density on X will increase and on H will decrease.
In the context of X-H---Y, 'H' forms a direct bond with 'X' while also engaging in a hydrogen bond with 'Y.' Given that both 'X' and 'Y' are electronegative elements with a tendency to attract electrons, the electron density is skewed toward them. In particular, because 'X' forms a direct bond with 'H,' it exerts a stronger pull on electron density, resulting in an increase in electron density on 'X' and a corresponding decrease in electron density on 'H.'