Thermodynamics
Latent Heat
Heat required for phase change at constant temperature.
Variables
QJ
Heat
Heat for phase change
In SI units: kg·m²/s²
mkg
Mass
Mass of substance
Allowed values: 0 or more
LJ/kg
Latent heat
Heat per unit mass
In SI units: m²/s²
Allowed values: greater than 0
Derivation
Q = mL where L is latent heat of fusion or vaporization.
Your notes
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Check value
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- m = 2 kg (Mass)
- L = 3 J/kg (Latent heat)
Result: Q = 6 J
Where this formula is listed
- Thermodynamics formulas, under Heat & Temperature, alongside Linear Thermal Expansion, Volume Thermal Expansion, Heat Conduction, Stefan-Boltzmann Law and Thermal Resistance.
- In the thermodynamics list it comes after Heat Capacity and before Linear Thermal Expansion.
- Thermodynamics formula sheet, one of 34 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Latent Heat formula?
Latent Heat is written Q = mL. Heat required for phase change at constant temperature. It belongs to Thermodynamics, under Heat & Temperature.
What are the units in Q = mL?
In SI units, Q is heat, measured in kg·m²/s²; m is mass, measured in kg; L is latent heat, measured in m²/s².
How is the Latent Heat formula derived?
Q = mL where L is latent heat of fusion or vaporization. The result is Q = mL.