Give the bond angles for each of the geometries in the preceding question.
Here, we are going to determine the bond angles for each geometry.
The molecular geometry of a molecule depends on (i) number of electron group around the central atom (ii) Number of bonding groups and lone pairs.
(a) two electron groups
Both the electron group is bonding pair electron.
The geometry of the molecule having two electron groups is Linear.
For example: BeH2, HCN and CO2
Therefore, the bond angle for Linear geometry is 180o.
(b) three electron groups
Three electron groups are bonding pair of electrons.
The geometry of the molecule having three electron groups is Trigonal Planar.
For example: COCl2, CO32-
Therefore, the bond angle for Trigonal planar geometry is 120o.
(c) four electron groups
Here, Four electron groups are bonding pair of electrons.
The geometry of the molecule having four electron groups is Tetrahedral.
For example: CH4,
Therefore, the bond angle for Tetrahedral geometry is 109.5o.