Understanding the types of intermolecular forces present in different substances helps us grasp their boiling points, solubilities, and overall physical properties. Let’s break down the intermolecular forces for each of the given substances:
1. Isopropyl Alcohol (C3H8O)
Isopropyl alcohol primarily exhibits hydrogen bonding due to its hydroxyl (–OH) group. This strong interaction occurs when the hydrogen atom attached to the oxygen forms a bond with an electronegative atom from another molecule. Additionally, van der Waals (London dispersion) forces are present, which are weaker forces resulting from temporary dipoles in molecules. Overall, isopropyl alcohol has:
- Hydrogen bonding
- Dipole-dipole interactions
- London dispersion forces
2. Hydrogen Iodide (HI)
Hydrogen iodide exhibits dipole-dipole interactions because it is a polar molecule, with the hydrogen atom being partially positive and the iodine atom being partially negative. In addition, hydrogen iodide will have London dispersion forces, though these are less significant compared to its dipole-dipole interactions. Therefore, the predominant intermolecular forces in hydrogen iodide are:
- Dipole-dipole interactions
- London dispersion forces
3. Krypton (Kr)
Krypton is a noble gas and is nonpolar, meaning it does not have significant dipole moment or participate in hydrogen bonding. The only type of intermolecular force present in krypton is London dispersion forces. These forces arise from the momentary dipoles induced in the atoms due to fluctuations in electron density.
- London dispersion forces
In summary, each substance has distinct intermolecular forces that contribute to their unique physical properties. Isopropyl alcohol features hydrogen bonding, hydrogen iodide relies on dipole-dipole interactions, and krypton interacts solely through London dispersion forces.