Question

The dipole moment of KCl is $3.336\times {10}^{29}$ coulomb metre which indicates that it is highly polar molecule.The interatomic distance between $K^{+}$ and $C{l}^{-}$ in this molecule is $2.6\times {10}^{10}$ m. The dipole moment of KCl molecule is, if there were opposite charges of one fundamental unit located at each nucleus.

• A. $4.165\times {10}^{29}$ coulomb metre.
• B. $2.985\times {10}^{29}$ coulomb metre.
• C. $3.545\times {10}^{29}$ coulomb metre.
• D. $Noneofthese$

Answer 1

The correct option is A $4.165\times {10}^{29}$ coulomb metre.

Dipole moment assuming 100 % ionic character would be the product of its charge and the inter atomic distance. It would be
$4.8\times {10}^{-10}esu\times 2.6\times {10}^{-8}cm=12.47\times {10}^{-18}esucm$
But $1esucm=3.3356\times {10}^{-12}Cm$
Hence, the dipole moment assuming 100% ionic character is
$12.47\times {10}^{-18}esucm\times 3.3356\times {10}^{-12}=4.165\times {10}^{-29}Cm$