What is the density of carbon dioxide gas if 0.297 g occupies of 150.0 mL?

Which of these is a physical property

How do dying stars contribute to the formation of planets

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?