Is energy released during the reaction of sodium and water?If yes what type of energy is present in sodium is converted to heat energy? If no then what actually happens, is energy created?(Note law of conservation of energy states that energy can neither be created nor be destroyed)
Answers
Energy is the driving force for the universe. Energy is a quantitative property of a system which may be kinetic, potential, or other in form. There are many different forms of energy. One form of energy can be transferred to another form. The laws of thermodynamics govern how and why energy is transferred. Before the different types of energy resources and their uses are discussed, it is important to understand a little about the basic laws of energy.
The Three Laws of Thermodynamics
There are three laws of thermodynamics. The first law of thermodynamics, also called conservation of energy, states that the total amount of energy in the universe is constant. This means that all of the energy has to end up somewhere, either in the original form or in a different from. We can use this knowledge to determine the amount of energy in a system, the amount lost as waste heat, and the efficiency of the system.
The second law of thermodynamics states that the disorder in the universe always increases. After cleaning your room, it always has a tendency to become messy again. This is a result of the second law. As the disorder in the universe increases, the energy is transformed into less usable forms. Thus, the efficiency of any process will always be less than 100%.
The third law of thermodynamics tells us that all molecular movement stops at a temperature we call absolute zero, or 0 Kelvin (-273oC). Since temperature is a measure of molecular movement, there can be no temperature lower than absolute zero. At this temperature, a perfect crystal has no disorder.
When put together, these laws state that a concentrated energy supply must be used to accomplish useful work.
Work
Many of us commonly think of energy as the ability of a system to do work. Work is a force applied to an object over a certain distance, such as pulling or pushing a wooden block across your desk. Your muscles do work when they facilitate body movement. Units of work and energy are joules (J). One joule equals one Newton meter (N*m).
By definition, work is an energy requiring process. So, how do you describe energy? Energy is not a substance that can be held, seen, or felt as a separate entity. We cannot create new energy that is not already present in the universe. We can only take different types materials in which energy is stored, change their state, and harness the energy that escapes from the system in order to use it to do work for us. If the released energy is not used, it will escape and be "wasted" usually as heat.
Heat
Heat is the quantity of energy stored or transferred by thermal vibrations of molecules. At absolute zero, a system has no heat energy. Heat is additive. If two masses with heat energies of 5 joules and 10 joules are added together, the added masses will have a total heat energy of 15 joules. Heat and temperature should not be confused.
Temperature
The temperature of a system is the average vibrational energy of all the molecules within the system. Temperature is not additive. Putting two metal blocks that are 75o C together will leave the new system at the same temperature. Putting two masses that are 50o C and 100o C will make the new system somewhere between 50o C and 100o C. The temperature of which would be dependent on the masses and heat capacities of each added element.
When a fast-moving molecule collides with other molecules, it loses some of its kinetic energy to those surrounding molecules. Those molecules now have more energy than they had before. This extra energy is manifested as vibrations within the molecule. Thus, the temperature of the substance being hit will increase.