Law of Conservation of Energy:

In physical science, the law of conservation of energy states that the total energy that is produced from an isolated system remains constant and is said to be conserved. This means that the energy can neither be created nor be destroyed but it can only be transformed and transferred from one form to the other. Like for instance, chemical energy gets converted to kinetic energy when a stick of dynamite gets exploded. While adding up all the forms of released energy such as kinetic energy and potential energy the exact decrease in the weight of the chemical energy can be calculated. The conversion of energy is somewhat different from that of the conversion of mass. The second law of conservation of energy or thermodynamics states about the quality of the energy. According to the second law of thermodynamics, as energy is transferred or as it gets transformed more and number of it gets wasted. The law states that there is a natural tendency of any isolated system to get itself degenerated into a more disordered state. The third law of thermodynamics states that the entropy of a system gradually approaches towards a constant value as the temperature tends to approach towards zero. The law of conservation of energy states the behavior of energy about their form and their behavior of getting transferred between different objects. The law of conservation of energy can be observed in our daily life. For example the melting of ice cube experiences the process of first and second law of conservation of energy.

Endothermic process:

An endothermic process is defined as the process that absorbs the energy from its surroundings in the form of heat. The process may include chemical processes such as dissolving of ammonium nitrate in water or by the help of physical process such as melting of ice. The term endothermic process was coined by Marcellin Berthelot from the Greek roots endo meaning within and thermo meaning hot. An example of endothermic reaction can be stated as production of wood. Here the trees absorb radiant energy from the Sun and use it in endothermic reactions such as taking up CO2 and H2O  while releasing the energy in the form of heat and light to its surroundings.

Exothermic process:

The opposite of endothermic reaction is known exothermic reaction or exothermic process. The process includes releasing of energy in the form of heat or in the form of light, electricity or sound. Exothermic process includes two types of chemical reaction that are found in nature. Example burning of a candle where the net calories produced as a result of combustion exceeds the amount of calories that gets absorbed initially while lightning the flame and maintaining the flame by itself.

Conversion using heat units:

Heat flow is measured in terms of calorie or joule.

1 kilocalorie= 1 calorie = 1000 calories.

Heat changes are a type of chemical reaction. The conversion between a joule and a calorie is shown below:

1 J = 0.2390 cal or 1 cal = 4.184 J.