## General Chemistry: Principles and Modern Applications (10th Edition)

Since the electronegativity of $\mathrm{Cl}$ is much less than that of $\mathrm{F}$, the $\mathrm{Cl}$ in $\mathrm{OCl}_{2}$ has more positivity (blue color) than has $\mathrm{F}$ in $\mathrm{OF}_{2}$.