The NGOs Ethical and Unethical Policies

Pauli Exclusion Principle Definition

Pauli Exclusion Principle Definition The Pauli exclusion principle states no two electrons  (or other fermions) can have the identical quantum mechanical state in the same atom  or molecule. In other words, no pair of electrons in an atom can have the same electronic  quantum numbers n, l, ml, and ms. Another way to state the Pauli exclusion principle is to say the total wave function for two identical fermions is antisymmetric if the particles are exchanged. The principle was proposed by Austrian physicist Wolfgang Pauli in 1925 to describe the behavior of electrons. In 1940, he extended the principle to all fermions in the spin-statistics theorem. Bosons, which are particles with an integer spin, do not follow the exclusion principle. So, identical bosons may occupy the same quantum state (e.g., photons in lasers). The Pauli exclusion principle only applies to particles with a half-integer spin. The Pauli Exclusion Principle and Chemistry In chemistry, the Pauli exclusion principle is used to determine the electron shell structure of atoms. It helps to predict which atoms will share electrons and participate in chemical bonds. Electrons which are in the same orbital have identical first three quantum number. For example, the 2 electrons in the shell of a helium atom are in the 1s subshell with n 1, l 0, and ml 0. Their spin moments cannot be identical, so one is ms -1/2 and the other is ms 1/2. Visually, we draw this as a subshell with 1 up electron and 1 down electron. As a consequence, the 1s subshell can only have two electrons, which have opposite spins. Hydrogen is depicted as having a 1s subshell with 1 up electron (1s1). A helium atom has 1 up and 1 down electron (1s2). Moving on to lithium, you have the helium core (1s2) and then one more up electron that is 2s1. In this way, the electron configuration of the orbitals is written.

Military Essay Paper Example | Topics and Well Written Essays - 500 words

Military Paper - Essay Example The presence of homosexuals in the U.S. military remains a hot political debate. Homosexuals are serving the military for decades now. But they are the real threat to the discipline and high standard of moral of the soldiers. Liberals want gays to serve in the military and on the other hand conservatives wish to completely ban homosexuals. Serving members who have committed a homosexual conduct justify this by their own explanation. For Example they give the reason of being alone for a longer period of time, living with room mates in the remote areas for months and even for years. (Stewart, 28-32) But the fact is that this act can not be justified especially if committed by a soldier. Reports of women being abused and raped by the military personnel has also became a very big issue of the U.S. Military. This made women feel insecure when serving in the military. In most of the cases the men who are responsible are not punished, and they are simply given warning about not to do it aga in. This problem still persists today. New laws pertaining to the presence of homosexuals in the United States Military are made, which shows a compromise in the policy. This compromise was made because the presence of those service members who have an intent or propensity of engaging in a homosexual act creates a risk to the discipline, good order and high standard of morale of the soldiers. This new policy change is referred to as â€Å"don’t ask, don’t tell†. According to this new policy no one will be asked about their sexual interest when he or she is being recruited and he is also not allowed to tell anyone about his homosexual interests. This new change has worked well and has decreased the number of discharges due to homosexual conduct. (Stewart, 54) In order to protect the women from being abused or raped, there is a need of implementation