Quantity of Heat

Syllabus tag: KCSE | Physics | Form 3 | Topic 29 Quantity of Heat

Lesson objectives

By the end of this topic, you should be able to:

• Distinguish heat from temperature and define heat capacity.
• Define specific heat capacity and solve problems using Q = mcΔθ.
• Define specific latent heat of fusion and vaporisation.
• Explain the effects of pressure and impurities on melting and boiling points.

Summary

Heat is energy in transit; temperature is the degree of hotness. Specific heat capacity is the heat needed to raise 1 kg by 1 K, and Q = mcΔθ. During a change of state the temperature stays constant while latent heat is supplied, given by Q = mL.