Calorimeters are a device that can measure the heat that comes from burning an item. Simple Calorimeter
A simple calorimeter is used to detect the enthalpy change when a fuel is burned. The fuel is burnt to heat a specific mass of water and then measure its rise in temperature. The word calorimeter comes from the Latin phrase calor which means heat. A simple calorimeter just consists of a thermometer attached to a metal container full of water suspended above a combustion chamber. Below is a diagram of a simple calorimeter.
When measuring the energy produced from a compound, water is used to measure the amount of heat; this is because of its specific absorption of energy. The experiment above is very inefficient. This is because not all of the energy is absorbed by the water; some is absorbed by the air, while some is absorbed by the container holding the water. Also, the fuel may not have entirely reacted. Flame Calorimeter
A flame calorimeter is just a improved adaptation of the simple calorimeter. It includes the following features to help reduces heat loss even further: •
A spiral chimney made of copper
An enclosed flame
The flame burns in pure oxygen rather than in air
A bomb calorimeter is a type of constant-volume calorimeter used in measuring the heat of combustion of a particular reaction. Bomb calorimeters have to withstand the large pressure within the calorimeter as the reaction is being measured. Electrical energy is used to ignite the fuel, as the fuel is burning, it will heat up the surrounding air, which expands and escapes through a tube that leads the air out of the calorimeter. When the air is escaping through the copper tube it will also heat up the water outside the tube. The temperature of the water allows for calculating calorie content of the fuel. Pressurized with pure oxygen and containing a known mass of a sample and a small amount of water, it is submerged under a known volume of water...
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