The strongest type of intermolecular force in NH2CH3 is hydrogen bonding. Hydrogen bonding is an attractive force between molecules that occurs when a hydrogen atom covalently bonded to an electronegative atom, such as nitrogen, oxygen, or fluorine, forms a dipole-dipole interaction with another electronegative atom.
In the case of NH2CH3, the hydrogen bonding is happening between the hydrogen atom of the NH2 group and the nitrogen atom of the CH3 group. This is because the hydrogen atom is partially positively charged, while the nitrogen atom is partially negatively charged. This creates an attractive force between the two molecules, resulting in a stronger intermolecular force than other types of intermolecular forces.
In addition to hydrogen bonding, other intermolecular forces that can be present in NH2CH3 include London dispersion forces and dipole-dipole interactions. London dispersion forces are attractive forces between molecules caused by temporary induced dipoles. Dipole-dipole interactions are attractive forces between molecules that occur when two molecules with permanent dipoles interact.
In the case of NH2CH3, the dipole-dipole interaction is between the NH2 group and the CH3 group. This is because the nitrogen atom of the NH2 group is partially negatively charged, while the carbon atom of the CH3 group is partially positively charged. This creates an attractive force between the two molecules, resulting in a weaker intermolecular force than hydrogen bonding.
In conclusion, the strongest type of intermolecular force in NH2CH3 is hydrogen bonding. This is because the hydrogen atom of the NH2 group is partially positively charged, while the nitrogen atom of the CH3 group is partially negatively charged. This creates an attractive force between the two molecules, resulting in a stronger intermolecular force than other types of intermolecular forces.
