When carrying out a certain experiment, heat can propagate in three different ways: convection, conduction and irradiation.
When the material is in a liquid or gaseous state it will transfer heat by convection, this process consists of the propagation of heat by hot and cold currents that rise and fall, as we can see, the moving matter is what performs the distribution of heat. When we put a liquid to boil it boils when the heat is evenly distributed throughout the liquid part, the water starts to move and distributes the heat.
Conduction heat transfer occurs, for example, in metals such as aluminum, copper and iron. When the metal is heated, the particles that make it up are agitated and transfer heat to all the particles that make up the material. And it is not necessary for molecules to move for this transmission to occur, metals are good conductors of heat.
What would radiant heat transfer look like?
Consider that you are near a burning fireplace, your body receives heat from the fire without having to precisely touch it, is it magic? No, it's energy in the form of radiation. As an example we have the biggest phenomenon of every morning, which lights up and warms our planet, the Sun. Solar heat is responsible for life on Earth, if there was no heat transfer from this star, we would freeze to death.
Irradiation occurs from an emitter body to a receiver, in the case of the sun, it is the heat emitter and we are the receivers. This energy is called radiant energy, it propagates in space and is transferred by electromagnetic waves.
By Líria Alves
Graduated in Chemistry
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Source: Brazil School - https://brasilescola.uol.com.br/quimica/transferencia-calor-um-sistema.htm