Question

Which of the following has zero dipole moment?

Options

• Trans [Pt(NH₃)₂Cl₂]

• Cis [Pt(NH₃)₄ClBr]²⁺

• Trans [Pt(NH₃)(H₂O)Cl₂]

• Cis [Pt(NH₃)₂Cl₂)

Answer 1

Trans [Pt(NH₃)₂Cl₂]

Explanation:

\[\begin{array}{cc}
\phantom{..}\ce{Cl}\phantom{...}\ce{NH3}\phantom{}\\
\phantom{}\backslash\phantom{}/\phantom{}\\
\ce{Pt}\\
\phantom{}/\phantom{}\backslash\phantom{}\\
\phantom{}\ce{H3N}\phantom{...}\ce{Cl}\phantom{..}\\
\ce{Trans isomer}
\end{array}\]

The trans isomer has zero dipole moment as a result of the two opposite Pt - Cl and two Pt - NH₃ bond moments, which cancel each other.