Discover the Universe of an Atom - Essay Example

Chemical energy kinetic energy heat energy sound energy light energy heat energy chemical energy light energy heat energy.Week 1-DQ 2"Heat is a form of energy and energy is conserved. The heat lost by a system must be equal to the heat gained by the surroundings. Therefore, heat is conserved"Comment on the correctness/incorrectness of this passage. Correct the faults.Week1-DQ3The Bohr model for the atom has been set aside for the quantum mechanical model. However, what is the evidence that the Bohr model "works" Why has it been set asideAnswer:The evidence that Bohr's model works:The evidence that Bohr's model works is in the fact that the moon is able to move around its orbital without crashing to the continent like Australia and it is also supported by Millikan's Oil Drop experiment that explains how an atom can exist only in definite amounts of quanta, hence "stationary states.

" Why it is set aside for the quantum mechanical model: Bohr calculated an equation that gives simplistic values for the radii or energy level shell at which the electrons could orbit in a "stationary state" where there is neither emissions nor absorptions of energies explained by the discontinuous transition between the different energy level shells. This is what Bohr tries to explain in his formula below:-Bohr formula: hf = Ei - Ef n2i n2f If the quantum number is n, Ef = 1 E1 and Ei = 1 E1 where E1 is the energy of the atom in the first orbit.

Substituting each into Bohr's Formula we get hf = E1 X 1 - 1 n2i n2f Next substitute c / for f: n2i n2f Divide both sides by Plank's constant h times the speed of light c: 1 = E1 X 1 - 1 where h= Plank's constant, f= frequency, Eh, and Ef are approximately the initial and final energies of the atom in stationary states.(http://library.thinkquest.org/28582/history/bohr.htm )Week 1-DQ4Since energy relationships can be exactly calculated, the element Hydrogen can be said to be "solved".Why can't a multielectron element be solvedAnswer:Hydrogen has a mass of 1 hence its energy content can be calculated directly.

Moreover, Hydrogen has only one energy level hence when an electron is excited cannot move to another energy level.On the other hand, multi-electron elements have more electrons and more energy levels. Hence when electrons are excited can move from one energy level to another: either higher or lower and in the process energy is given out. Therefore, electrons are many hence energy relationships cannot be done directly or not "solved".(Nelson, p188)References