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Definition of sensitive heat, latent heat and specific heat
Sensitive heat
When heat added to or removed from a substance causes a change in temperature in the substance, this heat is called sensitive heat, an example:
If we have a glass of liquid water at 0ºC and we want to raise its temperature to 2ºC we will have to add a certain amount of heat, this heat that will cause this temperature rise will be sensitive heat.
Latent heat
Latent heat is that heat which added or removed from a substance, causes a change of state in it, from solid to liquid, from liquid to gas, from solid to gas, etc. This heat unlike the sensitive heat, does not cause a change of temperature, an example:
Starting from the same previous example, a glass of liquid water at 0ºC and wanting to change the state of this water to a solid state -ice-, we will have to extract a certain amount of heat to change its state, this heat necessary for this change of state will be latent heat, as a result we will have the same glass of water in the SOLID state and at the same temperature 0ºC since the change of temperature is always ‘taken care of’ by the sensible heat.
Differences between sensitive and latent heat. The first one causes a change of temperature without changing its state; the second one causes a state change without varying the temperature.
Specific heat
The specific heat of a substance is the amount of heat, which needs to be supplied to the unit of mass (1 kg) of that substance to raise its temperature by 1 degree, for example:
If we have 1 liter (1 kg) of water at 30ºC and we want to raise its temperature to 31ºC, we will need 1,000 calories (4,186 kJ), these 1,000 calories will be the specific heat of the water, if on the other hand we want to raise 10 degrees from 30ºC to 40ºC, the amount of heat needed will be 1,000 cal x 10 = 10,000 cal.
m = mass
Ce = specific heat
Tf = final temperature
Ti = initial temperature
Q = amount of heat
It should be noted, that the specific heat of each substance is different and this also varies according to its temperature, so it will not require the same energy to raise 1 kg of water 1 º C, that 1 kg of aluminum the same degree.
