MEASUREMENT OF THE SPECIFIC HEAT CAPACITY OF WATER

MEASUREMENT OF THE SPECIFIC HEAT CAPACITY OF WATER BY AN ELECTRICAL METHOD PRECAUTIONS • Ensure that the heating element is covered with water to avoid any loss of heat energy. • Ensure that the calorimeter is well insulated to avoid loss of heat energy. • Use a sensitive thermometer. • Ensure that room temperature is midway between the initial and final temperatures of the water. Energy supplied = (mcΔθ)cal + (mcΔθ)water

MEASUREMENT OF THE SPECIFIC HEAT CAPACITY OF WATER BY THE METHOD OF MIXTURES Precautions • Transfer the copper quickly to reduce heat loss. • Ensure that the calorimeter is well insulated to avoid loss of heat energy. • Use a sensitive thermometer. Energy lost by copper rivets = energy gained by the water + the copper calorimeter mcccΔθ = mwcwΔθ + mcalccΔθ

MEASUREMENT OF THE SPECIFIC LATENT HEAT OF FUSION OF ICE PRECAUTIONS • Ensure that the ice is dried. • Use warmed water at the start of the experiment to reduce overll heat loss. This also helps the ice to melt more quickly speeding up the expt. • Use a well insulated calorimeter to avoid loss or gain of heat to the surroundings. (mcΔθ)cal + (mcΔθ)water = (ml)ice + (mcΔθ)melted ice

MEASUREMENT OF THE SPECIFIC LATENT HEAT OF VAPORISATION OF WATER PRECAUTIONS: • Ensure that only steam (not water) enters the water in the calorimeter. Use a "steam trap“. • If the water in the calorimeter is initially cooled to 10 °C below room temperature and then heated to 10 °C above room temperature the heat gains and heat losses approximately cancel each other out. • Use a well insulated calorimeter to avoid loss or gain of heat to the surroundings mlsteam + mcΔθcondensed_steam = mcΔθcal + mcΔθwater

To Calibrate a mercury thermometer PRECAUTIONS • Heat the water very slowly so that it is easy to take temperature and length readings simultaneously. • Have your eye level with the liquid columns when taking temperature and length readings to avoid parallax error. Measure the length of the mercury column and the temperature. Plot a graph of temperature against length.