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

The Correct Option is A

The given chemical scenario involves an electronegative element X, a hydrogen atom H, and another electronegative element Y forming a molecule X-H-----Y. Here, both X and Y are electronegative, meaning they have a strong tendency to attract electrons towards themselves.

1. Understanding Electronegativity: Electronegativity is a measure of an atom's ability to attract shared electrons in a chemical bond. Elements with high electronegativity, like fluorine, oxygen, and chlorine, tend to draw electrons closer to themselves, thus increasing their electron density.
2. Analyzing the Bond Formation:
   • The bond X-H suggests that element X is bonded to hydrogen.
   • Hydrogen, being less electronegative than both X and Y, will tend to lose electron density to its neighboring electronegative atom, in this case, X.
3. Effect on Electron Density:
   • Because X is electronegative, it will draw electron density away from H, thereby reducing the electron density on H.
   • Consequently, X will gain electron density, as it is pulling electrons towards itself from H.
4. Concluding Explanation:
   • In the bond X-H, X increases in electron density, while H decreases in electron density, due to X's greater electronegativity.

Thus, the correct answer is: "Electro density on X will increase and on H will decrease".