Question

A water molecule has an electric dipole moment $7 \times 10^{-30} C - m$ when it is in vapour state. The distance between the center of positive and negative charge of the molecule is

• A. $5 \times 10^{-11} m$
• B. $2 \times 10^{-11} m$
• C. $4.1 \times 10^{-1} m$
• D. $4.375 \times 10^{-11} m$

Answer 1

Answer: (D)

$P=q \times 2 a$
Distance between the center is a
$P=q \times a$
$a=\frac{7 \times 10^{-30}}{1.6 \times 10^{-19}}$
$=4.375 \times 10^{-11} m$