For this problem, we are being asked to determine the primary intermolecular forces present in H2O and CH3OH
In solutions, recall that the main contributing factor for solubility is intermolecular forces. There are several types of intermolecular forces (IMF):
1. Ion-dipole interaction – occurs between an ion and a polar covalent compound; strongest IMF
2. Hydrogen bonding – occurs in compounds where hydrogen is directly connected to an electronegative element such as N, O, or F; 2nd strongest IMF
3. Dipole-dipole interaction – occurs between two polar covalent compounds; 3rd strongest IMF
4. Dispersion forces – occurs in all compounds and is the primary IMF exhibited by nonpolar compounds; weakest IMF
In this case, we need to do the following steps to determine H2O and CH3OH's IMF
Step 1: Determine the central atom in the molecule.
Step 2: Calculate the total number of valence electrons present.
Step 3: Draw the Lewis structure for the molecule.
Step 4: Determine the polarity and IMF of the molecule.
Water (H2O) and the alcohol methanol (CH3OH) are infinitely soluble in each other. The primary intermolecular force responsible for this is:
a. London-dispersion forces
e. van der Waals forces