Assume that some protein molecule, in its folded native state, has one favored conformation. but when it is denatured, it becomes a "random coil", with many possible conformations. part a what must be the sign of δs for the change: native → denatured?

ΔS will be positive.

Explanation:

Denaturation may be defined as the loss of the biological activity of protein by changing the physical conditions of protein. Protein can be denatured by increasing temperature, pH and salts.

Entropy may be defined as the randomness of molecule. The entropy increase with increase in the randomness of the substance. Since, protein has been denatured, the random coil confirmation increase. This means the randomness of protein has been increased, this increase the entropy and makes it more positive.

Thus, entropy becomes more positive.