The start of 2016 as been a rocky one. Stock markets are on a downward trend. And just yesterday, the bombings in Indonesia has lead to greater insecurity in the region. How do these bomb attacks work? Why do they possess so much energy for destruction?
Chemical Energy is the energy kept in the bonds of atoms and molecules. This form of energy is released in a chemical reaction. While the chemical energy is being released, there is a byproduct of heat that is produced from the reaction. This is an exothermic reaction. In other cases heat is also absorbed when the chemical reaction is taking place.
The chemical energy released or absorbed as a result of a reaction between chemical reactants is equal to the difference between the amount of energy of the products and the reactants, if there is no change in temperatures i.e. the initial and final temperatures are similar. It is possible to estimate this change in temperatures from the bond energies of the different chemical bonds in the reactants and products. Alternatively, it can be calculated from the internal energies of the reactant molecules and of the product molecules. Furthermore, the change in the internal energy of a chemical process is equal to the heat exchanged if it is measured under conditions of constant volume and the same initial and final temperatures.
Some common types of stored chemical energies are batteries, coal, petroleum, food, natural gas, and biomass. In the process of releasing chemical energy, the substance that had stored the chemical energy is transformed into a totally new substance in the process. That is the reason as to why the chemical energy is referred to as the potential of a chemical substance to get transformed through a chemical reaction into other form(s) of a substance.
Examples of processes or reactions that release chemical energy
1. When a bomb explodes, the chemical energy stored in the bomb is lost to the surroundings in form of thermal energy, sound energy as well as kinetic energy.
2. When burning firewood, the chemical energy stored in the wood is released and converted to thermal energy, which makes the fireplace feel warmer, and light energy (there is a glow in the fireplace). Also, it is good to notice that there is the formation of the ashes which is a totally new substance.
3. Another process that release chemical energy is the food that we consume. The food contains stored chemical energy, which is released during the process of digestion. When the food is being digested, the molecules in the food are broken down into smaller ones and in the process, energy is produced.
As what was taught during our Physics tuition classes, especially in the Work Energy Power chapter, there are many more energy conversions that you can quote from our daily life events.