Practice: Determine the bond angle for the thiocyanate ion, SCN–.
Bond Angles result from surrounding elements and lone pairs around the central element positioning themselves at an optimal distance.
Concept #1: Ideal Bond Angles
Ideal Bond Angle is the optimal angle elements take in order to minimize repulsion.
Example #1: If the H–C–H angle within the CH4 molecule is 109.5º, what is the H–N–H bond angle within NH3?
The more lone pairs on the central element, the more compressed the bond angle, and the greater the deviation from an ideal bond angle.
Concept #2: Bond Angles and Electron Groups.
Example #2: Determine the F–I–F bond angle for the following ion: IF4–.
Practice: Determine the bond angle for the thiocyanate ion, SCN–.
Practice: In the PCl3F2 molecule the chlorine atoms exist in the equatorial positions and the fluorine atoms exist in the axial positions. Based on this information, predict the Cl–P–Cl bond angle.
Practice: Determine the O–N–O bond angle for N2O4, which exists as O2N–NO2.
