What is Calorific value and how to determine the calorific value

1. What is Calorific value?

The heat released when a unit weight of oil is completely burned under specified conditions. In the International System of Units (SI), it is expressed in joule.

2. The pricinple of bomb calorimeter?

The calorific value via the Oxygen bomb calorimeter is measured by the heat obtained from the sample, compared with the heat obtained from combustion of a reference material such as benzoic acid. A known amount of sample is burnt in a high pressure oxygen atmosphere within a vessel or “bomb”. The energy released by this combustion is captured by the calorimeter unit and the resulting temperature change within the absorbing medium is recorded. The heat of combustion of the sample is then calculated by multiplying the temperature rise in the calorimeter by a previously determined energy equivalent or heat capacity determined from previous tests with a reference material.

3. How to determine the calorific value by bomb calorimeter?

• The initial temperature of water noted

• Combustion is started by passing electric current through the platinium wire.Thats raise the temperature of water,it is recorded from the temperature

• By knowing the heat capacity of thermometer and also raise in temperature.the heat envolved can be calculated