Which of the following is not true regarding the formation of a dipeptide?

a. a molecule of water is produced
b. two amino acids are joined together
c. a double bond forms between carbon and nitrogen
d. a protein is formed

The correct answer is option C. "a double bond forms between carbon and nitrogen".

Explanation:

A dipeptide are formed by the binding of two amino acids. The chemical bond that binds the two amino acids is called peptide bond, and when enough amino acids are joined together a protein is formed. It is not true that a double bond forms between carbon and nitrogen during the formation of a dipeptide, carbon and nitrogen are bond by a single covalent bond.

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pesticide

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.