Specific heat capacity

Different materials like water, aluminium, steel or glass need different amounts of energy to heat them up and they give out different amounts of energy when they cool down.

Energy needed to heat them up depends upon   a property of the material x mass x temperature rise

This property of the material is called the “specific heat capacity” abbreviated to SHC.  So that we can easily compare different materials, we use a standard mass and a standard temperature rise.

Most commonly the definition is:

The specific heat capacity is the energy needed to heat 1 kilogram of the substance by 10C

in symbol form

E = cmΔθ      or   c =   E/mΔθ

The two diagrams below show the standard experimental equipment used to measure SHC in the laboratory.  In the video lesson below the diagrams I use more everyday equipment to perform a similar experiment.

Measuring the specific Heat Capacity of a solid

 

Measuring the specific Heat Capacity of a liquid

You can download a pdf of notes on SHC here: Specific heat capacity  

Specific heat capacity video lesson

Example calculation on specific heat capacity

We have started with 1.120 Kg of water at 6.50C

after one minute with an average power of 2674 watts

the total energy input is 60 x 2674 = 160440 joules

this energy input has raised the temperature to 36.50C  a temperature rise of 300C

The SHC     =       Energy input/mass x temperature rise

c =   E/ mΔθ   .     =     160440/1.12 x 30        =    4775 jKg-1C-1

The generally accepted value is 4186 jKg-1C-1