How many water molecules would be produced in making a polypeptide that is 14 amino acids long?

13 Amino acids have a common structure where there is a carboxyl group at one end (CO2H) and a amino group at the other (NH2). There's also a side chain that's unique for every amino acid. When two amino acids are joined in producing a polypeptide, the carboxyl and amino groups are linked with the release of a water molecule. So in this problem, you simply need to count the number of links, which will be 1 less than the number of amino acids in the chain. Hence, for a 14 amino acid chain, you need 13 links which produced 13 water molecules.

How do we find the answer?