Explain in terms of particle volume, why a sample of helium can not be compressed by a piston to a volume of zero. please can someone explain

The mass of a neutron is equal to the mass of a proton plus the mass of an electron. true or false false true

Which diagram shows the correct way to represent an ionic compound of magnesium oxide?

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?