The developed structural formula is also attached.
Explanation:
The IUPAC name, <em>2-hydroxypropanoic acid</em>, lets you predict the structural formula for <em>lactic acid</em>.
<em>2-hydroxy</em> means that there is a OH functional group attached to the second carbon atom of the chain.
<em>Propan</em> prefix means that the molecule has 3 carbon atoms.
<em>oic</em> suffix means that it is a carboxylic acid, this is it contains the COOH functional group.
Hence, in conclusion the structural form of lactic acid is:
C³H₃ - C²H - C¹OOH
|
OH
I used the superscripts just to show the number of the carbon atom in the chain.
The formal structural formula does not contain such superscripts it is just:
CH₃ - CH - COOH
|
OH
A more developed structural formula will show the distribution of the atoms in the space. I have also attached a picture with the developes structural formula.
The intermolecular forces between water molecules are stronger than those between oxygen molecules. In general, the bigger the molecule, the stronger the intermolecular forces, so the higher the melting and boiling points.