Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Ex Input:
Most of the gray matter is on the surface of the brain, surrounding white matter.

Ex Output:
Most of the gray matter is on the surface of the brain, surrounding what other type of matter?


Ex Input:
The pressure of ocean water increases rapidly as the water gets deeper.

Ex Output:
What property of ocean water increases rapidly as the water gets deeper?


Ex Input:
The atom is the representative particle in pure metals.

Ex Output:
What is the representative particle in pure metals?