The measure of the quantity of matter would be mass. Mass is measured in kilograms. I hope this helped!:)
Convection is the circular motion that occurs as hotter air or liquid increases when the cooler air or liquid drops down, and has faster moving molecules, rendering it less dense. Convection currents within the earth shift layers of magma, and currents are formed by convection in the ocean.
More mass and less difference
Rocket fuel will and smoke will emit from the thrusters.