An engineer is testing a cryogenic storage dewar containing liquid nitrogen at its boiling point of 77 K.
Over a 24-hour period, a minor thermal leak results in the vaporisation of 420 g of liquid nitrogen.
The specific latent heat of vaporisation of nitrogen is 1.99 × 105 J/kg.
Calculate the thermal energy absorbed by the nitrogen during this vaporisation process.
36 exam-style questions on Edexcel GCSE Physics 14.2 Specific heat capacity and latent heat, covering 14.2.1 Heating, temperature and changes of state, 14.2.2 Specific heat capacity and specific latent heat, 14.2.3 Specific heat capacity calculation, 14.2.4 Specific latent heat calculation, and 14.2.5 Reducing energy transfer through thermal insulation. Each one has a worked solution and a mark scheme showing where the marks go.