Specific Latent Heat of Fusion

Specific latent heat of fusion, L of a substance is the quantity of heat which is required to change one unit mass of the substance from solid to liquid without any change of temperature at the melting limit.

Its unit is JKg-1.

This condition occurs at the melting point of the solid.

For example, 336000J of heat is required to change 1Kg of ice at 0°C.
Therefore the latent heat of fusion, L for ice is 336 000 JKg-1.

when liquid solidifies, the specific latent heat of fusion will be released.

This condition occurs at the freezing limit of a liquid.

For example, when 1 Kg of water at 0°C solidifies to become 1 Kg of ice of 0°C, 336 000 J of heat are released.

If m Kg of solid or liquid is involved, the quantity, Q of heat absorbed or released is Q = mL
where Q = quantity of heat that is absorbed or released
m = mass of substance
L = latent heat of fusion

Below are examples of substance with its specific latent heat

• 
  
• Aluminum 3.96x105 JKg-1.
  
• Copper 2.05x105 JKg-1.
  
• Iron 2.67x105 JKg-1.
  
• Lead 0.23x105 JKg-1.
  
• Brass Unknown 
  
• Magnesium 3.7x105 JKg-1.
  
• Zinc 1.1x105 JKg-1.