• 1 mol of beryllium • 1 mol of salt
• 1 mol of water
• 1 mol of hydrogen
Which statement is true about these substances?
They have exactly the same mass.
O They have different numbers of particles.
O They have the same number of atoms.
0 They have different masses.

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?