Endothermic chemical reactions
Substance transformations that only take place when energy is added in the form of heat are called endothermic chemical reactions - do my php assignment . The reaction products have a higher energy content than the starting materials. The heat of reaction Q has a positive sign.
An example of such an endothermic reaction is the formation of nitrogen monoxide from nitrogen and oxygen. This reaction "consumes" heat - online chemistry problem solver . The electrolysis of water to oxygen and hydrogen is also an endothermic reaction. The following applies to all endothermic reactions: The energy contained in the reaction products is greater than the energy present in the starting materials.
Heat of combustion
The heat of combustion indicates how much heat is released when a certain amount of fuel (wood, coal, petrol, ...) is burnt.
Formula symbol: Q
Unit: one joule (1 J)
The heat of combustion depends on the amount of fuel and its calorific value. The heat released when substances burn is called the heat of combustion - do my homework club . The heat of combustion indicates how much heat is released when a certain amount of fuel (wood, coal, petrol, ...) is completely burnt.
The greater the quantity (mass) of fuel, the greater the heat of combustion,
- the greater the quantity (mass) of the burnt material and
- the greater its calorific value.
For solid fuels, e.g. coal, the mass is usually given in kilograms. For liquid fuels, e.g. petrol, the usual unit is litres. The quantity of a gas is usually given in cubic metres, whereby this value refers to the standard state (pressure of 1013 mbar, temperature of 0 °C).
More information:
