Convection cells occur because of the movement of heat. On which physical property of matter is this based? volume mass specific gravity density

Answer: density

Convection is the circular cycle of rising and falling of a liquid or gas as it becomes hotter or cooler. When a liquid or gas becomes hotter, its density decreases, which causes the substance to rise. After rising, the substance loses heat and becomes cooler, which increases its density. This causes the substance to fall or sink to the bottom.