Question

Dipole moment of $H_{2}O$ is 1.85 D. If bond angle is ${1.5}^o$ and O - H bond length is $0.94\mathring{A}$, determine magnitude of the charge on the oxygen atom in the water molecule.
From the bond angle and vector moment $\mu =e\times l$. Thus, e (charge) can be determined in $esu$.

• A. $3.23\times {10}^{-10}$
• B. $5.43\times {10}^{-10}$
• C. $4.43\times {10}^{-10}$
• D. None of these

Answer 1

The correct option is A $3.23\times {10}^{-10}$

$AB=BCcos{52.5}^o$
$=0.94\times 0.609=0.572\mathring{A}$
$=0.572\times {10}^{-8}cm$
Also, $\mu =e\times AB$
$\therefore e=\frac{\mu }{AB}=\frac{1.85\times {10}^{-18}esucm}{0.572\times {10}^{-8}cm}$
$=3.23\times {10}^{-10}esu$