Heat of Crystallization from Molten Salt

Material Small flask, burner, thermometer, tripod and clamps sodium acetate hydrate. 

Procedure Half-fill a flask with sodium acetate hydrate and melt the salt completely through the use of the burner. Leave the molten matter to cool in the air, insert a thermometer and measure the temperature. Add one crystal of sodium acetate hydrate to the liquid, observe first, and measure the temperature again. 

Observation The molten matter crystallizes instantly when the seeding crystal is added. The temperature of the crystalline mass rises during this procedure to more than 50°C. The test can be repeated through continued melting and cooling down. 

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