When a hot dog is cooked, is that a physical change or chemical change

How will the emission of an alpha particle affect the atomic number of an atom

What is a possible quantum number set for an electron in the 3s orbital of a magnesium atom

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?