coal tar
This process is called DIFFUSION.
any gas
Diffusion is the movement of molecules from a region of high concentration to one of low concentration. As NO2 is heavier than air, diffusion takes place and hence after some time the brown colour is seen in jar containing air. Geethanjali Somisetty
Because the particles of the gas are in a state (sometimes called an excitable state) which allows random movement, they are vibrating and continually bouncing against each other, and moving faster if the gas is heated. Smoke rises from a fire because it is heated. Since the hotter particles are hitting their neighbours harder and faster the gas needs to take up more space. It expands. It also becomes lighter or less dense. it begins to rise, forming convection currents. Warm air rises; cold air sinks.
The movement of air on and out the lungs is called respiration. The movement of air into the lungs is called inhalation (inspiration). The movement of air out of the lungs is called exhalation (expiration).
Convection
air turbulence
the movement in the air or vibrations
No
It is called wind.
It is called wind.
wind
The transmission of heat requiring the movement of a liquid or a gas is called convection.
Ventilation
The movement of heat in gases and liquids are called convection.
Air