Dear student
The calorimeter consists of two vessels - the outer vessel and the inner vessel
Air between both vessels acts as heat insulator which ensures heat is not exchaged between inner and outer vessel. The calorimeter is also equipped with a thermometer and a stirrer. The thermometer measures the temperature of the liquid in the inner vessel. The stirrer is used to distribute heat in the vessel. A ring made of insulating fiber material holds the inner vessel in the center of the outer vessel. The calorimeter has an insulating cover with holes for the stirring rod and thermometer.
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