# Some small ice blocks are dried with blotting paper

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The exact temperature is read and recorded. Some small ice blocks are dried with blotting paper and then added to the water in the calorimeter. The mixture is gently and continuously stirred. Each piece of ice is allowed to melt completely before the next is added. When the temperature of the mixture is about 5 0 below room temperature, the exact temperature is read with a thermometer. The calorimeter with its content is reweighed to find the mass of ice added.
The specific latent heat capacity of ice is then calculated as follows: Mass of calorimeter and stirrer = (kg).Mass of calorimeter + stirrer + water = (kg).Mass of calorimeter + stirrer + water + ice = (kg).Initial temperature of water = Final temperature of mixture = Specific heat capacity of calorimeter = Specific heat capacity of water = 4200 Specific latent heat of fusion of ice =
Mass of water = .Heat required to melt the ice = ) Heat required to raise the melted ice from 0= ) x 4200 x Heat loss by the calorimeter and water in cooling from to =Since the heat gained by ice = heat lost by the calorimeter and water, we can write= since,
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Precautions 1Only dry ice pieces should be used.2Ice should be added in small quantities at a time.3The mixture should be gently and continuously stirred to obtain an even temperature of the mixture4The final temperature should be about the same amount below vroom temperature as the initial temperature is above room temperature. In the way we can largely compensate for the heat exchange between the calorimeter and its content and the surrounding air.5The calorimeter should be lagged.
Expansion and contraction on fusion Water expands on freezing to ice, because of this expansion,I.A glass bottle containing water, cracks when the water freezesII.Ice is less dense than water and so float on waiter with nine-tenths of its volume submerged in water.III.Similarly ice contracts on melting to water. The ice directly below the wire melts because the increased pressure lowers the melting point of the ice, hence the wire falls through the water formed. Above the water, decrease in pressure rises the freezing point of the melted ice and the water freezes again. On refreezing it liberates latent heat which is conducted by the wire to melt more ice beneath it. The process is repeated till the wire passes right through the ice block without cutting it into two. When we press two pieces of ice. blocks one against the other, they stick together. The increased pressure lowers the melting point of ice. The melted ice flows away to places of lower pressure. There, it refreezes, binding the two pieces of ice together.
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