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Chm 303 Course Guide
COURSE GUIDE CHM 303 INORGANIC CHEMISTRY III Course Team Professor Phd Aliyu (Course Writer) - Department of Chemistry University of Abuja Prof. Sulaiman o. Idris (Course Reviewer) - Department of Chemistry Ahmadu Bello University Zaria Dr Emeka C. Ogoko - (Head of Department) - NOUN NATIONAL OPEN UNIVERSITY OF NIGERIA CHM 303 COURSE GUIDE © 2021 by NOUN Press National Open University of Nigeria Headquarters University Village Plot 91, Cadastral Zone NnamdiAzikiwe Expressway Jabi, Abuja Lagos Office 14/16 Ahmadu Bello Way Victoria Island, Lagos e-mail: [email protected] URL: www.nou.edu.ng All rights reserved. No part of this book may be reproduced, in any form or by any means, without permission in writing from the publisher. Printed 2021 ISBN: 978-978-058-092-6 ii CHM 303 COURSE GUIDE CONTENTS PAGE Introduction………………………………………………. iv What You Will Learn in This Course…………………….. iv Course Aim………………………………………………… iv Course Objectives…………………………………………. v Working through this Course……………………………… v The Course Materials……………………………………… v Study Sessions……………………………………………… vi Presentation Schedule……………………………………… vii Assessment………………………………………………… vii Tutor Marked Assignments ………………………………… vii Final Examination and Grading……………………………. vii Course Marking Scheme…………………………………… viii Facilitators/Tutors and Tutorials…………………………… viii iii CHM 303 COURSE GUIDE INTRODUCTION Inorganic Chemistry III course (CHM 303) is one of the core courses for the Bachelor of Science degree programme in Chemistry. It is a three- credit unit course at 300 level of the National Open University of Nigeria, designed for students with a fair background knowledge in inorganic Chemistry II course. This course gives an over view of the physical and chemical properties of the elements of the periodic table in addition to the extraction and purification of metals. -
Group 18 - the Elements
Group 18 - The Elements ! All found in minute quantities in air. • Argon is most abundant (and cheapest), comprising 0.934% of air by volume. ! Although rare on earth, helium is the second most abundant element in the universe (H, 76%; He, 23%), being a major component of stars. ! All radon isotopes are short-lived and are continuously being produced by natural decay processes. 222 • Longest lived isotope is Rn (á, t½ = 3.825 days). ! Condensed phases are held together by van der Waals forces, which increase smoothly down the group. Element b.p. (K) I (kJ/mol) He 4.18 2372 Ne 27.13 2080 Ar 87.29 1520 Kr 120.26 1351 Xe 166.06 1169 Rn 208.16 1037 Helium ! Helium is found in certain natural gas deposits (e.g., in Kansas), where it probably forms as a result of radioactive decay in the rocks. ! Because of its low boiling point, it is used widely in cryogenic applications. • Also used in airships (e.g., Goodyear blimp) and as a balloon filler. • Used as a fill gas for deep diving, because it is less soluble in blood than nitrogen, thus avoiding the "bends." ! The 4He isotope has the lowest know boiling point, 4.12 K, at which point it is called He-I. • On cooling to 2.178 K a phase transition to He-II occurs. • He-II has an expanded volume, almost no viscosity, and is superconducting. • He-II can readily flow uphill to equalize volumes in adjacent vessels. • It cannot be stored in glass Dewars, because it leaks through glass into the evacuated space, posing an explosion risk. -
Periodic Trends in the Main Group Elements
Chemistry of The Main Group Elements 1. Hydrogen Hydrogen is the most abundant element in the universe, but it accounts for less than 1% (by mass) in the Earth’s crust. It is the third most abundant element in the living system. There are three naturally occurring isotopes of hydrogen: hydrogen (1H) - the most abundant isotope, deuterium (2H), and tritium 3 ( H) which is radioactive. Most of hydrogen occurs as H2O, hydrocarbon, and biological compounds. Hydrogen is a colorless gas with m.p. = -259oC (14 K) and b.p. = -253oC (20 K). Hydrogen is placed in Group 1A (1), together with alkali metals, because of its single electron in the valence shell and its common oxidation state of +1. However, it is physically and chemically different from any of the alkali metals. Hydrogen reacts with reactive metals (such as those of Group 1A and 2A) to for metal hydrides, where hydrogen is the anion with a “-1” charge. Because of this hydrogen may also be placed in Group 7A (17) together with the halogens. Like other nonmetals, hydrogen has a relatively high ionization energy (I.E. = 1311 kJ/mol), and its electronegativity is 2.1 (twice as high as those of alkali metals). Reactions of Hydrogen with Reactive Metals to form Salt like Hydrides Hydrogen reacts with reactive metals to form ionic (salt like) hydrides: 2Li(s) + H2(g) 2LiH(s); Ca(s) + H2(g) CaH2(s); The hydrides are very reactive and act as a strong base. It reacts violently with water to produce hydrogen gas: NaH(s) + H2O(l) NaOH(aq) + H2(g); It is also a strong reducing agent and is used to reduce TiCl4 to titanium metal: TiCl4(l) + 4LiH(s) Ti(s) + 4LiCl(s) + 2H2(g) Reactions of Hydrogen with Nonmetals Hydrogen reacts with nonmetals to form covalent compounds such as HF, HCl, HBr, HI, H2O, H2S, NH3, CH4, and other organic and biological compounds. -
Interhalogen Compounds
INTERHALOGEN COMPOUNDS Smt. EDNA RICHARD Asst. Professor Department of Chemistry INTERHALOGEN COMPOUND An interhalogen compound is a molecule which contains two or more different halogen atoms (fluorine, chlorine, bromine, iodine, or astatine) and no atoms of elements from any other group. Most interhalogen compounds known are binary (composed of only two distinct elements) The common interhalogen compounds include Chlorine monofluoride, bromine trifluoride, iodine pentafluoride, iodine heptafluoride, etc Interhalogen compounds into four types, depending on the number of atoms in the particle. They are as follows: XY XY3 XY5 XY7 X is the bigger (or) less electronegative halogen. Y represents the smaller (or) more electronegative halogen. Properties of Interhalogen Compounds •We can find Interhalogen compounds in vapour, solid or fluid state. • A lot of these compounds are unstable solids or fluids at 298K. A few other compounds are gases as well. As an example, chlorine monofluoride is a gas. On the other hand, bromine trifluoride and iodine trifluoride are solid and liquid respectively. •These compounds are covalent in nature. •These interhalogen compounds are diamagnetic in nature. This is because they have bond pairs and lone pairs. •Interhalogen compounds are very reactive. One exception to this is fluorine. This is because the A-X bond in interhalogens is much weaker than the X-X bond in halogens, except for the F-F bond. •We can use the VSEPR theory to explain the unique structure of these interhalogens. In chlorine trifluoride, the central atom is that of chlorine. It has seven electrons in its outermost valence shell. Three of these electrons form three bond pairs with three fluorine molecules leaving four electrons. -
Chemistry of the Noble Gases*
CHEMISTRY OF THE NOBLE GASES* By Professor K. K. GREE~woon , :.\I.Sc., sc.D .. r".lU.C. University of N ewca.stle 1tpon Tyne The inert gases, or noble gases as they are elements were unsuccessful, and for over now more appropriately called, are a remark 60 years they epitomized chemical inertness. able group of elements. The lightest, helium, Indeed, their electron configuration, s2p6, was recognized in the gases of the sun before became known as 'the stable octet,' and this it was isolated on ea.rth as its name (i]A.tos) fotmed the basis of the fit·st electronic theory implies. The first inert gas was isolated in of valency in 1916. Despite this, many 1895 by Ramsay and Rayleigh; it was named people felt that it should be possible to induce argon (apy6s, inert) and occurs to the extent the inert gases to form compounds, and many of 0·93% in the earth's atmosphere. The of the early experiments directed to this end other gases were all isolated before the turn have recently been reviewed.l of the century and were named neon (v€ov, There were several reasons why chemists new), krypton (KpVn'TOV, hidden), xenon believed that the inert gases might form ~€vov, stmnger) and radon (radioactive chemical compounds under the correct con emanation). Though they occur much less ditions. For example, the ionization poten abundantly than argon they cannot strictly tial of xenon is actually lower than those of be called rare gases; this can be illustrated hydrogen, nitrogen, oxygen, fl uorine and by calculating the volumes occupied a.t s.t.p. -
Mean Amplitudes of Vibration of Iodine Trifluoride
Note 333 Mean Amplitudes of Vibration of Iodine Table 1. Calculated mean amplitudes of vibration (in A) of IF3. Trifluoride HK) MI-F(ax) «I-F(eq) u F(ax)...F(ax) MF(ax)...F(eq) E. J. Baran 0 0.0448 0.0401 0.057 0.057 Centro de Qufmica Inorgänica (CEQUINOR/CONICET, 100 0.0448 0.0401 0.057 0.058 UNLP), Facultad de Ciencias Exactas, 200 0.0460 0.0405 0.058 0.062 Universidad Nacional de La Plata, C. Correo 962, 298.16 0.0489 0.0420 0.061 0.068 1900-La Plata, Argentina 300 0.0489 0.0420 0.061 0.068 400 0.0528 0.0444 0.066 0.075 Reprint requests to Prof. E. J. B.; 500 0.0568 0.0474 0.071 0.082 E-mail: [email protected] 600 0.0609 0.0500 0.075 0.089 700 0.0648 0.0529 0.080 0.095 Z. Naturforsch. 56a, 333-334 (2001); 800 0.0686 0.0558 0.085 0.101 received January 12, 2001 900 0.0723 0.0586 0.089 0.107 1000 0.0759 0.0613 0.094 0.113 Mean amplitudes of vibration of IF3 have been calculated from vibrational spectroscopic data in the temperature range between 0 and 1000 K. Bond properties of the molecule are dis cussed on the basis of these results. Some comparison with relat Table 2. Comparison of the mean amplitudes of vibration (in A ed species are made. and at 298. 16 K) of the three isostructural XF3 species. -
1 Unit 4.4 Chemistry of Non-Transition Elements Few Facts of Halogens: A
Unit 4.4 Chemistry of Non-transition Elements Few facts of halogens: a) Ionisation energy of halogens is very high. This indicates that it has very little tendency to lose electrons. Due to gradual increase in size, it decreases down the group. b) The halogen molecules are held by weak Vander Waals forces, which increase down the group. This is responsible for the solid state of iodine. c) Chlorine has highest electron affinity in the group. Due to small size, fluorine has lower electron affinity than chlorine. d) All halogens are coloured as shown below: Halogens Fluorine Chlorine Bromine Iodine Colour Light Yellow Greenish Yellow Reddish Yellow Dark Violet The origin of colours of halogens is due to the absorption of visible light which excite the outermost electron to a higher energy level. Fluorine, being very small in size require very large excitation energy (obtained from the blue or violet part) of light, hence light yellow. Iodine being very large in size, the required lower excitation energy is obtained by absorption of yellow part of light. Interhalogen compounds: Halogen elements have different electro-negativity. Due to this they combine with each other to form covalent compounds (binary). “The binary compounds formed by halogens amongst themselves are known as Inter- halogen compounds”. These compounds have general formula; XYn, where n = 1, 3, 5 & 7. Ternary compounds of halogens are not known; as such a complex molecule might be unstable. Classification: Various types of inter-halogen compounds are tabulated below: Element Fluorine Chlorine Bromine Iodine Fluorine ------ ----- ----- ----- Chlorine ClF, ClF3, ClF5 --- --- --- Bromine BrF, BrF3, BrF5 BrCl --- --- Iodine IF, IF3, IF5, IF7 ICl, ICl3 IBr --- From the above table, the following points may be noted: • The inter-halogen compounds may be regarded as the halide of the more electronegative halogen. -
5.04 Principles of Inorganic Chemistry II Fall 2008
MIT OpenCourseWare http://ocw.mit.edu 5.04 Principles of Inorganic Chemistry II Fall 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. Chemistry 5.04 (F08) Practice Problem Set Practice vibrational and MO problems for the exam 1. Chatt prepared the dinitrogen complexes, trans-Mo(N2)2(PR3)4 in which the surprising result of two π-acid ligands coordinate trans to each other. Build the MO diagram for the complex. Draw the frontier d-orbital MOs and indicate the HOMO and LUMO orbitals. 2. Shown below are two electronically different metal carbides. Use MO arguments to address the following: a. Draw the HOMO for each complex. b. Explain the vacant site trans to the carbide atom in the square pyramidal, Ru complex. c. How many pi electrons are donated from the anilides into the metal in the moly complex (assume that for each sp2 hybirdized N-atom the tert-butly group point up, towards the apical carbide, and the aryl groups point down). Do the anilides and carbide compete for π symmetry orbitals on moly? d. Estimate the relative acidity of both carbide-carbon atoms. Which of these acids will protonate the carbide: MeC6H5, HCPh3, H3CCOOH, H(OEt2)B[3,5-C6H3(CF3)2] (answer yes or no for each acid/carbide combination)? 8 3. The synthesis of uranocene, [(η -C8H8)2U], is considered as the beginning of modern organoactinide chemistry. Organoactinides are distinguished by covalent interactions between the 5f orbitals of the 2– actinoids as well as the 6d orbitals. -
The Elements.Pdf
A Periodic Table of the Elements at Los Alamos National Laboratory Los Alamos National Laboratory's Chemistry Division Presents Periodic Table of the Elements A Resource for Elementary, Middle School, and High School Students Click an element for more information: Group** Period 1 18 IA VIIIA 1A 8A 1 2 13 14 15 16 17 2 1 H IIA IIIA IVA VA VIAVIIA He 1.008 2A 3A 4A 5A 6A 7A 4.003 3 4 5 6 7 8 9 10 2 Li Be B C N O F Ne 6.941 9.012 10.81 12.01 14.01 16.00 19.00 20.18 11 12 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 3 Na Mg IIIB IVB VB VIB VIIB ------- VIII IB IIB Al Si P S Cl Ar 22.99 24.31 3B 4B 5B 6B 7B ------- 1B 2B 26.98 28.09 30.97 32.07 35.45 39.95 ------- 8 ------- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 4 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.47 58.69 63.55 65.39 69.72 72.59 74.92 78.96 79.90 83.80 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 5 Rb Sr Y Zr NbMo Tc Ru Rh PdAgCd In Sn Sb Te I Xe 85.47 87.62 88.91 91.22 92.91 95.94 (98) 101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 6 Cs Ba La* Hf Ta W Re Os Ir Pt AuHg Tl Pb Bi Po At Rn 132.9 137.3 138.9 178.5 180.9 183.9 186.2 190.2 190.2 195.1 197.0 200.5 204.4 207.2 209.0 (210) (210) (222) 87 88 89 104 105 106 107 108 109 110 111 112 114 116 118 7 Fr Ra Ac~RfDb Sg Bh Hs Mt --- --- --- --- --- --- (223) (226) (227) (257) (260) (263) (262) (265) (266) () () () () () () http://pearl1.lanl.gov/periodic/ (1 of 3) [5/17/2001 4:06:20 PM] A Periodic Table of the Elements at Los Alamos National Laboratory 58 59 60 61 62 63 64 65 66 67 68 69 70 71 Lanthanide Series* Ce Pr NdPmSm Eu Gd TbDyHo Er TmYbLu 140.1 140.9 144.2 (147) 150.4 152.0 157.3 158.9 162.5 164.9 167.3 168.9 173.0 175.0 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Actinide Series~ Th Pa U Np Pu AmCmBk Cf Es FmMdNo Lr 232.0 (231) (238) (237) (242) (243) (247) (247) (249) (254) (253) (256) (254) (257) ** Groups are noted by 3 notation conventions. -
17.2.3 Interhalogen Compounds(65-67)
Previous Page 824 The Halogens: Fluorine, Chlorine, Bromine, Iodine and Astatine Ch. 17 MF, < MCl, < MBr, < MI,. By contrast for number of halogen atoms: these ions will be less-ionic halides with significant non-coulombic considered in subsequent sections (pp. 835, 839). lattice forces (e.g. Ag) solubility in water Related to the interhalogens chemically, are follows the reverse sequence MI, < MBr, < compounds formed between a halogen atom MCl, < MF,. For molecular halides solubility and a pseudohalogen group such as CN, SCN, is determined principally by weak intermolecular N3. Examples are the linear molecules ClCN, van der Waals' and dipolar forces, and dissolution BrCN, ICN and the corresponding compounds is commonly favoured by less-polar solvents such XSCN and XN3. Some of these compounds have as benzene, CCl4 or CS2. already been discussed (p. 319) and need not Trends in chemical reactivity are also apparent, be considered further. A microwave studyf6') e.g. ease of hydrolysis tends to increase shows that chlorine thiocyanate is ClSCN (angle from the non-hydrolysing predominantly ionic Cl-S-C 99.8') rather than ClNCS, in contrast to halides, through the intermediate halides to the cyanate which is ClNCO. The corresponding the readily hydrolysable molecular halides. fluoro compound, FNCO, can be synthesized Reactivity depends both on the relative energies by several low-temperature routes but is not of M-X and M-0 bonds and also, frequently, on stable at room temperature and rapiCly dimerizes kinetic factors which may hinder or even prevent to F2NC(0)NC0.(69) The chemistry of iodine the occurrence of thermodynamically favourable azide has been reviewed(70)- it is obtained as reactions. -
GROUP 7 Halogen the Group of Halogens Is the Only Periodic Table
GROUP 7 Halogen The group of halogens is the only periodic table group that contains elements in all three familiar states of matter at standard temperature and pressure. All of the halogens form acids when bonded to hydrogen. Most halogens are typically produced from minerals of salts. The middle halogens, that is, chlorine, bromine and iodine, are often used as disinfectants. The halogens are also all toxic. Characteristics Chemical The halogens show trends in chemical bond energy moving from top to bottom of the periodic table column with fluorine deviating slightly. (It follows trend in having the highest bond energy in compounds with other atoms, but it has very weak bonds within the diatomic F2 element molecules.) Halogen bond energies (kJ/mol)[4] X X2 HX BX3 AlX3 CX4 F 159 574 645 582 456 Cl 243 428 444 427 327 Br 193 363 368 360 272 1 I 151 294 272 285 239 Halogens are highly reactive, and as such can be harmful or lethal to biological organisms in sufficient quantities. This high reactivity is due to the high electronegativity of the atoms due to their high effective nuclear charge. They can gain an electron by reacting with atoms of other elements. Fluorine is one of the most reactive elements in existence, attacking otherwise-inert materials such as glass, and forming compounds with the heavier noble gases. It is a corrosive and highly toxic gas. The reactivity of fluorine is such that, if used or stored in laboratory glassware, it can react with glass in the presence of small amounts of water to form silicon tetrafluoride (SiF4). -
Reactions of Alkylamino- and Dialkylaminotriphenylphosphonium
Reactions of Alkylamino- and Dialkylaminotriphenylphosphonium Halides with Halogens and Interhalogen Compounds; Formation of Alkylaminotriphenylphosphonium Polyhalides Hans Zimmer*, Madhusudan Jayawant, Adel Amer**, and Bruce S. Ault Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, USA Z. Naturforsch. 38b, 103-107 (1983); received September 20, 1982 Halides, IR Spectra, Raman Spectra Alkylamino- and cycloalkylaminotriphenylphosphonium halides react with elemental halogens or interhalogen compounds to afford alkylamino- or cycloalkylaminotriphenyl- phosphonium trihalides. The stability of these trihalides depends on the cation as well as the trihalide anion. The assignment of a trihalide structure to these compounds was based on elemental analysis and on IR- and Raman spectroscopic evidence. Most stable are the tribromide and [1X2]° salts. During all reactions involving N-alkylamino- and N-cyclo- alkylaminotriphenylphosphonium halides and elemental halogens an N-halogenation of the cation was not observed. Introduction [Ph3P-N-alk] ®Bre 0 ATtJ >- (2) K2-IN n In a series of papers we demonstrated the syn- Br thetic utility of alkylaminotriphenylphosphonium halides and the corresponding phosphinimines [Ph3P-N-alk] ®Br e [la-d]. It was shown that alkyl- [la] and cyclo- alkyltriphenylphosphinimines could be alkylated NR2 with iodomethane or -ethane to the corresponding strong OHQ e (3) phosphonium salts which upon hydrolysis gave high [Ph3P-N-alk] ®Br yields of secondary amines. Recently this reaction NR2 was extended to synthesize arylalkylamines by Ph3P=0 + R2N-NHalk alkylating aryltriphenylphosphinimines [2]. In or- (R = alkyl) der to further explore the synthetic utility of alkylaminotriphenylphosphonium salts we planned However, instead of N-bromination taking place, to N-brominate these salts in order to obtain the polyhalide formation was observed (eq.