Quantum Theory's Role in Mineral Chemistry: Electronic Structure & Behavior, Slides of Nutrition

Download Quantum Theory's Role in Mineral Chemistry: Electronic Structure & Behavior and more Slides Nutrition in PDF only on Docsity! Chemical Properties of Minerals II Basic Coordination Chemistry Docsity.com Quantum theory gives us insight into the electronic structure of atoms and allows us to rationalize the biological behavior of minerals Docsity.com The Basics Docsity.com Insights into the Electronic Structure of Atoms Li Fe Ba Ca White lt Emission Spectra of Elements Z 20 56 26 3 Energy is being emitted discontinuously Pauli: electron exists in two different states Intrinsic electron spin Docsity.com Electrons are arranged in a very specified manner around the nucleus of atoms Conclusions: Quantum theory: “the electronic energy of atoms are quantizied….meaning they can only take on certain discrete energy values”. A direct indication of the arrangement of electrons around a nucleus is ionization energies…the energy required to remove an electron from a gaseous neutral atom. Docsity.com The following rules apply to orbitals Rule: At most, two electrons may occupy an orbital (or suborbital) and they must be of opposite spin Rule: s orbitals are spherical, with energy that varies only with distance from the nucleus. At most 2 electrons may occupy an S orbital. Rule: p orbitals extended along the major X, Y and Z axis designated px, py and pz. Each holds 2 electrons, or 6 electrons to occupy the P orbital. The energy varies with both distance and direction Rule: Orbitals are designated s, p, d, and f and adhere to the following: s = spherical, 2 electrons p = sausage shape extending along x, y, and z axis, 6 electrons d = 5 degenerate orbitals along and between axes, 10 electrons f = (not a concern) Rule: d orbitals cover all space both along and between the axes. Their configuration is that of 5 degenerate (equal energy) and hold at most 10 electrons Docsity.com The following rules apply to quantum states or atoms and orbitals Rule: Atoms with a principle quantum number n = 1 have only a 1s orbital. Examples are hydrogen and helium. Rule: Quantum states vary with atomic number, i.e., number of electrons Rule: Atoms with n = 2 have s and p orbitals Rule: Atoms with n = 3 have s, p, and d orbitals Rule: 4s orbitals are at a lower energy level than 3d and fill before 3d Rule: Atoms with 4s and 3d orbitals when ionizing lose 4s first Docsity.com Hund’s rule: The lowest energy state of an atom is achieved when there is maximum utilization of the surrounding space by the occupying electrons. Pairing of electrons in an orbital is recognized as a higher energy state than single electrons of the same spin state occupying the orbitals. This does not apply to s orbitals. Pauli exclusion principle: No two electrons in an atomic orbital may share the same set of quantum numbers. This rule led to the realization that electrons in the same orbital must be of opposite spins. Two Major Rules in Chemical Physics that impinge on the behavior of minerals Docsity.com 2p orbitals. At the second quantum level orientation also becomes a factor in deciding orbital energy. Because there are 3 orientations existing simultaneously, a p orbital can hold a maximum of 6 electrons, 2 of opposite spin in each Shapes are the same, but differ in orientation Docsity.com ‘Table 8-2 Ground-state electron configurations for the first 10 elements Electron configuration iss Pictorial representation re o 2s 2p a SSS ie? 152252 ise 22 15°25?2p1 15?2s?2p2 15?25?263 15?2s?2p4 15225295 152252268 GCC CQO e@|e@|O © POC /|OCO|eO C|©|C|OC/O C|SO/|C|©@ GIOVE Docsity.com Principal Quantum Number (n =1, 2, 3) Iron 1s22s22p63s23p64s23d6 No. of occupying electrons Subshell (s,p,d,f) s = 2 p = 6 d = 10 f = 14 At. No. = 26 At. Wt.= 55.85 Argon [Ar]4s23d6 Docsity.com Class Exercise Atomic numbers of Potassium and Calcium are 19 and 20, respectively. Outer electrons are in the M shell (n = 3). Determine the electronic configurations of potassium and calcium and determine their most likely ionized form Docsity.com K = 1s 2s 2p 3s 3p 3d 4s Ca = 1s2 2s2 2p6 3s2 3p63d 4s2 Solution: When n = 3, the atom must contain s, p, and d subshells and 3 energy states. But, recall that the 4s subshell with 2 electrons is of a lower energy state than the 3d subshell and will fill first The most stable form occurs when both metals lose their 4s electrons. Thus: K+ and Ca2+ 2 2 6 2 6 1 [Ar]4s1 and [Ar]4s2 Z = 19 Z = 20 Docsity.com Macrominerals Liew 3$ -4 35s t H adden a 3 | 4 5 6 7 a Li | Be Microminerals Bi) ¢| Nie } ut 2 1 iti 1 3 | 4 | 16 wea ae First ee series all} ede 3d lio | 2 > , ; 4 1 2} mf} 2 28 | 29 | 30 41 32 | 33 | & 1} x | ca | Se | Ti | V | Ce Mn | Fe | Co Ni | Cu | Zn | Ga| Ge! As | Se a 4 i) 49 0 SI 52 1} pb} S In | Sn| Sb] Te 5 | 86 | 81 | 62 | ea | a i| Cs | Ba Tl | Pb| Bi | Po Fs] we] x] Bs] #5] FeJo 103 im 105 1065 | tO) Lr | Unq} Unp ri 4 1. Why do Ca2+, Mg2+, and Zn2+ exist only as +2 ions? Li+, Na+ and K+ as +1 ions? Ca = [Ar] 4s2 Mg = [Ne] 3s2 Zn = [Ar] 3d104s2 Li = [He] 2s1 Na = [Ne] 3s1 K = [Ar]4s1 Docsity.com Tetrahedral Square planar Octahedral Docsity.com Glu 117 Thr 199 His 64 —_ _e- Glu 106 1 VY His 96 1 \ 1 3? = Cd 0 Backbone 244 4 ’ ‘ iS His 119 Gln 92 Znat the Active Site of Carbonic Anhydrase y Docsity.com