What is the correct reaction for the dissociation (ionization) for a weak acid?

What is an example of a physical property?

When a scientific theory has been tested and proved by the scientific community, it becomes a law

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?