Bond angles and intermolecular forces present?

You can give the approximate value of those angles by looking at the hybridization of the two adjacent carbon atoms.

For angle #alpha#, the carbon atom, which belongs to a carboxyl group, #-"C"("O")"OH"#, is surrounded by three regions of electron density

• a single bond to the oxygen atom that belongs to the hydroxyl group, #-"OH"#
• a double bond to the other oxygen atom
• a single bond to another carbon atom

This means that the carbon atom has a steric number equal to #3#, and thus uses #3# hybrid orbitals to form the aforementioned bonds.

As a result, this carbon atom will be #"sp"^2# hybridized, which implies that the #alpha# angle is approximately #120^@#.

For angle #beta#, the carbon atom, which belongs to a methyl group, #-"CH"_3#, is surrounded by four regions of electron density

• a single bond to another carbon atom
• three single bonds to hydrogen atoms

This carbon has a steric number equal to #4#, and thus uses #5# hybrid orbitals to form the aforementioned bonds.

As a result, this carbon atom will be #"sp"^3# hybridized, which implies that the #beta# angle is approximately #109.5^@#.

This can be seen by looking at a molecule of pyruvic acid

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Now, a pyruvic acid molecule is polar because of the presence of the carboxyl group and of the carbonyl group, #-"C=O"#.

This means that it exhibits dipole - dipole interactions due to the existence of permanent dipoles.

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Moreover, because pyruvic acid has a hydrogen atom directly bonded to an oxygen atom in the hydroxyl group, it can act as a hydrogen bond donor.

The molecule can also act as a hydrogen bond acceptor due to the presence of the carbonyl group, which means that pyruvic acid can form hydrogen bonds.

Finally, all molecules, regardless if they are polar or non-polar, exhibit London dispersion forces due to random variations in the distribution of their electron clouds.