Specific latent heat – measuring fusion and vaporization of water

PhysicsThermal Physics & GasesAges 17–18

An electric heater of power P heats m kg of ice from −10 °C until it has all melted, boiled and vaporized. A thermometer and a stopwatch give a T(t) graph with two flat sections at 0 °C and 100 °C. From the duration of these plateaus students calculate λ = P·Δt/m and L = P·Δt/m, compare them with 3.34·10⁵ J/kg and 2.26·10⁶ J/kg, and see the effect of heat losses.