Which of the listed properties are the same for the elements carbon (c), nitrogen (n), and oxygen (o)?

hint: look at your periodic table.

number of protons
number of energy levels
number of neutrons
number of valence electrons

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?