Question

Which is the more effective buffer at physiological pH, a solution of 0.1 M glycylglycine or a solution of 0.2 M glycine?

Short answer

The 0.2 M glycine solution will act as a more effective buffer thanthe glycine peptide chain solution.

Step-by-step solution

Buffer solution

The buffer solution pH exhibits a small change in incorporating a small quantity of acid/base. The compound comprising an equal amount of positive and negative charge serves as a good buffer.

Identifying the amino acid that functions as a more effective buffer 

The compound contains two groups that function as a buffer, one amino group and a carboxylic acid group. So, the compound with a higher concentration serves as an effective buffer.

Hence, the 0.2 M glycine having more concentration than 0.1 M glycylglycinefunctions as an effective buffer.

The preparation of buffer solution with the solution of the glycine peptide chain and 0.2 M glycine solution are compared by using the positive and negative charges in the compounds.