What type of solids have regular geometric pattern?

[TT0]

So there was this question:

Which sample demonstrates particles arranged in a regular geometric pattern?

A. CO2(g)
B. CO2(s)
C. CO2(l)
D. CO2(aq)
E. None of the above

I chose E because I thought that covalent molecules, when solid, would be arranged in a random pattern, especially since this is a non-polar molecule. But apparently they will be arranged in a regular geometric pattern because the answer is B. So could someone confirm the answer and also tell me when solids have regular geometric pattern? Are there any rules?

 

[Bystander]

"Amorphous" (without structure) solids have no regular pattern and can be recognized by lack of a sharp melting point.

 

[TT0]

Ok, so is solid covalent molecules arranged in a regular geometric pattern?

 

[Borek]

Ok, so is solid covalent molecules arranged in a regular geometric pattern?

In most cases yes, covalent molecules on solidification will produce a crystal, with a regular pattern of molecules.

 

[TT0]

Interesting, does this happen even with non-polar molecules?

 

[PietKuip]

Interesting, does this happen even with non-polar molecules?

Probably all solids are crystalline at thermal equilibrium.
There does not seem to be a mathematical proof, but there are no known exceptions.

 

[TT0]

Ok thanks