Which of the following conditions MUST be true for the entropy of a pure solid to be zero?

Question

a) T must be 0 K
b) The solid must be crystalline and not amorphous
c)the solid must be perfectly ordered
d) the solid form must be an element

Answer 1

T=0K
if
S=0 (s is entropy)

Answer 2

It can be more than one of these choices, its a "check all that apply" question. Are there any other options that must apply for S=0??

Answer 3

See here:

http://en.wikipedia.org/wiki/Residual_entropy