Chemical Bonding And Molecular Structure Question 538
Question: $ H_2O $ is dipolar, whereas $ BeF_2 $ is not. It is because [CBSE PMT 1989; 2004]
Options:
A) $ H_2O $ is linear and $ BeF_2 $ is angular
B) $ H_2O $ is angular and $ BeF_2 $ is linear
C) The electornegativity of F is greater than that of O
D) $ H_2O $ involves hydrogen bonding whereas $ BeF_2 $ is a discrete molecule
Show Answer
Answer:
Correct Answer: B
Solution:
The overall value of the dipole moment of a polar molecule depends on its geometry and shape i.e., vectorial addition of dipole moment of the constituent bonds water has angular structure with bond angle 105° as it has dipole moment. However $ BeF_2 $ is a linear molecule since dipole moment summation of all the bonds present in the molecule cancel each other.