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Specific heat, sensible heat, and latent heat are physical quantities:
The specific heat of a substance is the amount of heat that must be supplied to a unit mass of that substance to raise its temperature by one unit. That amount varies greatly depending on the temperature the substance is at before heat is applied to it. For example, it takes one calorie to increase water at room temperature by one degree, but it takes only 0.5 calorie to increase the temperature of ice to -5 degrees by one degree. Specific heat also depends on atmospheric pressure. The same substance at a lower atmospheric pressure has a lower specific heat. The examples below are valid for a temperature of 25 degrees and a pressure of 1 atmosphere.
The sensible heat It is the amount of heat that a body can receive without affecting its molecular structure. If the molecular structure does not change, the state (solid, liquid, gas) does not change. Since the molecular structure does not change, a change in temperature is observed, which is why it is called sensible heat.
The latent heat is the energy (heat) necessary for a substance to change phase (state). If the change is from solid to liquid it is called heat of fusion. If the change is from liquid to gas it is called the heat of vaporization. When heat is applied to a substance that has reached the temperature where it changes state, it is impossible for the temperature to increase, it simply changes state. For example, if heat continues to be applied to boiling water, it will never exceed 100 ° C. Depending on the substance, latent heat can usually be measured in calories per gram or in kilojoules per kilogram (KJ).
Examples of specific heat
- Water (in liquid state): 1 Calorie per gram to increase 1 ° C
- Aluminum: 0.215 calorie per gram
- Beryllium: 0.436 calorie per gram
- Cadmium: 0.055 calorie per gram
- Copper. 0.0924 calorie per gram
- Glycerin: 0.58 calorie per gram
- Gold: 0.0308 calorie per gram
- Iron: 0.107 calorie per gram
- Lead: 0.0305 calorie per gram
- Silicon: 0.168 calorie per gram
- Silver: 0.056 calorie per gram
- Potassium: 0.019 calorie per gram
- Toluene: 0.380 calorie per gram
- Glass: 0.2 calorie per gram
- Marble: 0.21 calorie per gram
- Wood: 0.41 calorie per gram
- Ethyl alcohol: 0.58 calorie per gram
- Mercury: 0.033 calorie per gram
- Olive oil: 0.47 calories per gram
- Sand: 0.2 calorie per gram
Examples of sensible heat
- Apply heat to water that is between 1 and 100 ° C
- Apply heat to tin that is less than 240 ° C
- Apply lead heat that is below 340 ° C
- Apply heat to zinc that is below 420 ° C
- Apply heat to aluminum that is less than 620 ° C
- Apply heat to bronze that is less than 880 ° C
- Apply heat to nickel that is below 1450 ° C
Examples of latent heat
Water: latent heat of fusion: 80 calories per gram (it takes 80 calories for one gram of ice at 0 ° C to become water), latent heat of vaporization: 540 calories per gram (it takes 540 calories for one gram of water at 100 ° C to become steam).
Steel: latent heat of fusion: 50 calories
Alumino: latent heat of fusion: 85 calories / 322-394 KJ; latent heat of vaporization: 2300 KJ.
Sulfur: latent heat of fusion: 38 KJ; latent heat of vaporization: 326 KJ.
Cobalt: latent heat of fusion: 243 KJ
Copper: latent heat of fusion: 43 calories; latent heat of vaporization: 2360 KJ.
Tin: latent heat of fusion: 14 calories / 113 KJ
Phenol: latent heat of fusion: 109 KJ
Iron: latent heat of fusion: 293 KJ; latent heat of vaporization: 2360 KJ.
Magnesium: latent heat of fusion: 72 calories
Mercury: latent heat of fusion: 11.73 KJ; latent heat of vaporization: 356.7 KJ.
Nickel: latent heat of fusion: 58 calories
Silver: latent heat of fusion: 109 KJ
Lead: latent heat of fusion: 6 calories; latent heat of vaporization: 870 KJ.
Oxygen: latent heat of fusion: 3.3 calories
Gold: latent heat of fusion: 67 KJ
Zinc: latent heat of fusion: 28 calories
