We need 4190 J to heat 1 kg of liquid water by one degree (Celsius or Kelvin).We need 2108 J to heat 1 kg of ice water by one degree (Celsius or Kelvin).The specific heat capacity is a material property, which equals 2108 J/(kg K) for ice water, 4190 J/(kg K) for liquid water and 1.996 J/(kg K) for steam.Therefore, we need 2264705 J to evaporate 1 kg of water (something that occurs at 100 ☌). Enthalpy of vaporization is a material property that equals 2264705 J/kg for water. If the phase change involves evaporation (converting liquid water to steam), the specific latent heat is called enthalpy of vaporization or latent heat of vaporization.Therefore, we need 334000 J of heat to melt 1 kg of water (which occurs at 0 ☌). Enthalpy of fusion is a material property that equals 334000 J/kg for water. If the phase change involves melting (converting ice to liquid water), the specific latent heat is called enthalpy of fusion or latent heat of fusion.There are some essential points to consider about the terms of the previous equations: The total heat ( Q total) is then the sum of the quantities associated with the latent and sensible heat: On the other side, taking it from 20 to 200☌ involves sensible and latent heat, as at some intermediate point (100☌), we require some additional energy (latent heat) to evaporate the water. For example, under atmospheric conditions, taking water from 20 to 30☌ only involves sensible heat.
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