Increasing Bond Angle in Cl2O, ClO2, ClO2-

Introduction:
The bond angles in a molecule are determined by the arrangement of the atoms and the electron pairs around the central atom. In order to determine the bond angle, we need to consider the electron pair repulsion theory, also known as VSEPR theory.

VSEPR Theory:
According to VSEPR theory, the electron pairs around the central atom in a molecule repel each other and try to maximize their distance from each other. This leads to specific molecular geometries and bond angles.

Cl2O (Dichlorine monoxide):
- Cl2O has a bent molecular geometry due to the presence of two lone pairs on the central oxygen atom.
- The electron pair repulsion between the two lone pairs pushes the bonding pairs closer together, resulting in a smaller bond angle.
- The bond angle in Cl2O is approximately 111 degrees.

ClO2 (Chlorine dioxide):
- ClO2 also has a bent molecular geometry due to the presence of one lone pair on the central chlorine atom.
- The lone pair repels the bonding pairs, causing them to move closer together and resulting in a smaller bond angle.
- The bond angle in ClO2 is approximately 118 degrees.

ClO2- (Chlorite ion):
- ClO2- has a trigonal planar molecular geometry due to the absence of any lone pairs on the central chlorine atom.
- In a trigonal planar arrangement, the bond angles are expected to be 120 degrees.
- Therefore, the bond angle in ClO2- is approximately 120 degrees.

Summary:
The correct order of increasing bond angle in Cl2O, ClO2, ClO2- is as follows:
1. ClO2- (120 degrees)
2. ClO2 (118 degrees)
3. Cl2O (111 degrees)

Conclusion:
The bond angles in Cl2O, ClO2, and ClO2- are determined by the arrangement of atoms and electron pairs around the central atom. The presence of lone pairs and the resulting electron pair repulsion affect the bond angles. Cl2O has the smallest bond angle due to the presence of two lone pairs, while ClO2- has the largest bond angle as it has no lone pairs.

Bond angle will be greater in Cl2O.