Experiment to find the specific latent heat of

Experiment to find the specific latent heat of fusion of ice

Method 1. Place some ice cubes in a beaker of water and leave until the mixture reaches 0 °C 2. Find the mass of the calorimeter mcal. 3. Half fill the calorimeter with water warmed to approximately 5 °C above room temperature. Find the combined mass of the calorimeter and water m 2. 4. Record the initial temperature θ 1 of the calorimeter plus water. 5. Crush and dry the ice cubes. 6. Add the pieces of dry crushed ice, a little at a time, to the calorimeter until the temperature of the water has fallen by about 10 °C. 7. Record the lowest temperature θ 2 of the calorimeter plus water plus melted ice. . 8. Find the mass of the calorimeter plus water plus melted ice m 3.

Results Mass of the calorimeter mcal = Mass of the calorimeter plus water m 2 = Mass of the water mw = m 2 – mcal = Initial temperature of the calorimeter plus water θ 1 = Final temperature of the calorimeter plus water plus melted ice θ 2 = Rise in temperature of the ice Δθ 1 = θ 2 – 0 °C = Fall in temperature of the calorimeter plus water Δθ 2 = θ 1 – θ 2 = Mass of the calorimeter plus water plus melted ice m 3 = Mass of the melted ice mi = m 3 – m 2 = Calculation mil + micwΔθ 1 = mcalccΔθ 2 + mwcwΔθ 2 Cc = 390 J/Kg. K Cw = 4180 J/Kg. K

Precautions 1. Crush and dry the ice so that the ice melts quickly and no water drops are added. 2. Start with water slightly above room temperature and finish slightly below room temperature to reduce overall heat loss. 3. Use a thermometer with a low specific heat capacity. Note If drops are added to the calorimeter, they have already lost their latent heat in the room and this is not accounted for in the formula.