Which of the following order of molecular force of attraction among given species is incorect ?

Options

A. `HI gt HBr gt Cl_(2)`
B. `CH_(3)Cl gt C Cl_(4) gt CH_(4)`
C. n-pentane `gt` iso-pentane `gt` neo-pentane
D. `OH_(2) gt O (CH_(3))_(2) gt OB r_(2)`

Explanation

To determine the incorrect order of molecular force of attraction among the given species, we need to analyze the types of intermolecular forces present in each compound. The species mentioned are H2O, OBr2, and OCH3 (which can be interpreted as CH3OH, methanol).

### Step-by-Step Solution:

1. **Identify the Intermolecular Forces**:
- **H2O (Water)**: Water exhibits strong hydrogen bonding due to the presence of highly electronegative oxygen atoms bonded to hydrogen atoms. This results in a significant attraction between water molecules.
- **OBr2 (Oxygen dibromide)**: OBr2 has dipole-dipole interactions because it is a polar molecule. The bromine atoms are less electronegative than oxygen, creating a dipole moment.
- **OCH3 (Methanol)**: Methanol (CH3OH) also exhibits hydrogen bonding due to the presence of the hydroxyl (-OH) group. It has both dipole-dipole interactions and hydrogen bonding.

2. **Compare the Strengths of Intermolecular Forces**:
- Hydrogen bonds are generally stronger than dipole-dipole interactions. Therefore, we can rank the strength of intermolecular forces as follows:
- H2O (strong hydrogen bonding) > OCH3 (hydrogen bonding and dipole-dipole) > OBr2 (dipole-dipole).

3. **Establish the Correct Order**:
- Based on the analysis, the correct order of molecular forces of attraction should be:
- H2O > OCH3 > OBr2.

4. **Identify the Incorrect Order**:
- If the given order was H2O > OBr2 > OCH3, this would be incorrect because OCH3 has stronger intermolecular forces than OBr2 due to hydrogen bonding.

### Conclusion:
The incorrect order of molecular force of attraction among the given species is:
- H2O > OBr2 > OCH3.