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General Chemistry - Phase Change

In a phase change diagram, the straight horizontal lines show how it takes heat for a substance to change its phase, and the slanted lines show how the temperature increases when heat is added. When a solid becomes a liquid it is called melting. The reverse is called freezing or fusion. The constant for melting or freezing is called the heat of fusion. When a liquid becomes a gas its called evaporation. A liquid evaporates when its vapor pressure is equal to the surrounding atmospheric pressure. The reverse is condensation. The constant for evaporating or condensing is called the heat of vaporization or the heat of condensation. When a solid directly becomes a gas it is called sublimation. The reverse is deposition. 

Specific heat :
Specific heat is the number of calories it takes to get a substance to raise its temperature by a degree. 

Rule number 14: Specific heat 

Heat equals mass times specific heat times change in temperature or Q= mcΔt.