Arrange the following ligands in the order of increasing field strength. $$ \begin{array}{ccccc}…
Arrange the following ligands in the order of increasing field strength.
$$
\begin{array}{ccccc}
\mathrm{H}_2 \mathrm{O} & \mathrm{CO} & \mathrm{NH}_3 & \mathrm{I}^{-} & \mathrm{F}^{-} \\
\text {I } & \text { II } & \text { III } & \text { IV } & \text { V }
\end{array}
$$
IV < V < I < III < II
IV < V < III < II < I
V < IV < III < I < II
IV < I < V < II < III
Solution
According to spectrochemical series the correct order of increasing field strength of ligands is
$
\mathrm{I}^{-} < \mathrm{F}^{-} < \mathrm{H}_2 \mathrm{O} < \mathrm{NH}_3 < \mathrm{CO} .
$