Which of the following will have the maximum dipole moment?

\(CH_3Cl\)

The correct answer is option 1. \(CH_3Cl\)

The dipole moment of a molecule is a measure of the separation of positive and negative charge. The greater the separation of charge, the larger the dipole moment.

In the molecules of \(CH_3Cl, CH_3Br,\) and \(CH_3I\), the halogen atom is more electronegative than the carbon atom, so there is a separation of charge between the carbon atom and the halogen atom. However, the difference in electronegativity between the carbon atom and the halogen atom decreases as the size of the halogen atom increases. Therefore, the dipole moment of \(CH_3Cl\) is the largest of the three molecules.

The dipole moment of \(CH_3Cl\) is 1.92 D, the dipole moment of \(CH_3Br\) is 1.87 D, and the dipole moment of \(CH_3I\) is 1.62 D.

Option (2): \(CH_3Br\)

The dipole moment of \(CH_3Br\) is 1.87 D, which is lower than the dipole moment of \(CH_3Cl\). This is because the difference in electronegativity between the carbon atom and the bromine atom is slightly smaller than the difference in electronegativity between the carbon atom and the chlorine atom.

Option (3): \(CH_3I\)

The dipole moment of \(CH_3\)I is 1.62 D, which is the lowest of the three molecules. This is because the difference in electronegativity between the carbon atom and the iodine atom is the smallest of the three molecules.

Option (4): \(CH_3F\)

The dipole moment of \(CH_3F\) is 1.84 D, which is lower than the dipole moment of \(CH_3Cl\). This is because the difference in electronegativity between the carbon atom and the fluorine atom is slightly smaller than the difference in electronegativity between the carbon atom and the chlorine atom.

Therefore, the correct option is (1) \(CH_3Cl\).