atomic structure and quantum numbers

The structure of an atom is the basic unit of matter consisting of a nucleus and its negatively charged electron cloud surrounding it. [1] The nucleus contains a mix of positively charged protons and electrically neutral neutrons (except in Hydrogen-1 which has no neutrons). The electrons in an atom bound to the nucleus by the electromagnetic force. Similarly, a collection of atoms can bind to each other to form a molecule. Atoms containing the number of protons and electrons of the same neutral, while containing the number of protons and electrons of different positive or negative and is ion. Atoms are grouped based on the number of protons and neutrons in the atomic nucleus. The number of protons in an atom determines the chemical element the atom, and the number of neutrons determine the isotope of the element.The term atom comes from the Greek, which means it can not be cut or something that can not be divided again. The concept of the atom as a component that can not be divided again was first proposed by the philosophers of India and Greece. In the 17th century and into the 18th, the chemists laid the foundations of this idea by showing that certain substances can not be broken down further using chemical methods. During the late nineteenth century and early twentieth century, physicists have managed to find the structure and subatomic components inside the atom, to prove that the 'atom' is not never be divided again. [1] The principles of quantum mechanics are used The physicists then successfully model the atom. [1]Relative to daily observations, the atoms are very small objects with masses as minor anyway. Atoms can only be monitored using special equipment such as tunneling microscope Microscopy. More than 99.9% of the mass of the atom is concentrated in the nucleus, the proton and neutron are almost the same mass. Each element has at least one isotope with unstable nuclei that can undergo radioactive decay. This can lead to transmutation that changes the number of protons and neutrons in the nucleus. Electrons are bound to the atom contains a number of energy cedar, or orbital, which is stable and can undergo transitions between these cedar by absorbing or emitting photons that match the energy difference between the levels. The electrons in the atom determines the chemical properties of an element and affect the magnetic properties of the atom.



Ban Pauli principle is the principle of quantum mechanics formulated by Austrian physicist Wolfgang Pauli in 1925. In its simplest form for electrons in a single atom, this rule states that no two electrons having the same quantum numbers. So if n, l, and ml both electrons are all the same, ms must be different, so that the two electrons have opposite spin. More generally, there is no two identical fermions (particles with fractional spin) may occupy the same quantum state simultaneously.



Periodic systems and rule Aufbau; Block s, p, d, and fThe link between the periodic table with electron configuration (Aufbau principle) can be seen as in the picture below.We can see that the Aufbau principle moves from left to right throughout the period, and then increased to the next period. Each period begins with a sub-shell and closed subshell ns np (n = number of periods).1s 2s 2p 3s, 3p 4s, 3d, 4p 5s, 4d, 5p 6s, 4f, 5d, 6p 7s, 5f, 6dPeriod 1 2 3 4 5 6 7Based on the type of electron orbitals occupied by the last elements in the periodic system is divided into blocks of s, p-block, d-block, and the block f.a. Block s: class IA and IIAS-block metal classified as active, except H and He. H classified as non-metallic, while the noble gases He classified.b. Block p: group IIIA to VIIIAP-block elements called representative because there are all kinds of metals, non-metals, and metalloids.c. Block D: group IIIB to IIBBlock D is also called transition elements, all belonging to the metal.d. Block f: lanthanides and actinides









1. The principal quantum number (n): realizing the trajectory of electrons in atoms.n has a price of 1, 2, 3, .....- N = 1 corresponds to the K shell- N = 2 correspond to the L shell- N = 3 corresponds to the skin M- And so onEach skin or any number of energy levels occupied by electrons. The number of electrons that can occupy maksimmm energy levels must satisfy the Pauli formula = 2N2.Example:skin-to-4 (n = 4) can be occupied by a maximum = 2 x 42 electrons = 32 electrons2. Azimuthal quantum number (l): indicate sub skin where the electron also shows sub skin which is a constituent of skin.Azimuthal quantum number have prices from 0 to (n-1).n = 1; l = 0; corresponding K shelln = 2, l = 0, 1; corresponding L shelln = 3; l = 0, 1, 2; appropriate skin Mn = 4; l = 0, 1, 2, 3; appropriate skin Nand so onSub leather prices vary is given a special name:l = 0; fit leather sub s (s = sharp)l = 1; fit leather sub p (p = principle)l = 2; fit leather sub d (d = diffuse)l = 3; fit leather sub f (f = fundamental)Magnetic quantum number (m): realizing the presence of one or several levels of energy in a sub shell. Magnetic quantum number (m) has a price (-l) to price (+ l).For:l = 0 (sub leather s), price m = 0 (having 1 orbital)l = 1 (p sub shell), price m = -1, O, +1 (have 3 orbitals)l = 2 (sub skin d), price m = -2, -1, O, +1, +2 (have 5 orbitals)l = 3 (sub kwit f), price m = -3, -2, O, +1, +2, +3 (has 7 orbitals)4. Spin quantum number (s): indicates the direction of rotation of the electron on its axis.In one orbital, maximum of 2 electrons can circulate and the two electron spins through the axis in the opposite direction, and each is priced spin +1 / 2 or -1 / 2.




Question :  according to the theory of quantum mechanics, electrons in the atom does not have a definite orbit, why?