CHEM 1120 1nd Edition Lecture 18 Outline of Last Lecture I. Titrationsa. Acid-Base indicatorsII. Solubility Equilibriaa. KspIII. Factors affecting solubilitya. Common ion effectb. pHc. Complex ion formationd. Amphoterism IV. Precipitation and Separation of IonsOutline of Current Lecture I. Classes of elementsa. Metalsb. Metalloidsc. NonmetalsII. Properties of NonmetalsIII. Review of Periodic propertiesa. Ionization Energyb. Electron Affinityc. Electronegativity d. Atomic Radiie. Periodic TrendsIV. Group 1A – Hydrogena. 3 isotopesb. 3 types of hydrogen chemistryc. Properties of hydrogend. Hydrogen productionV. Noble Gases – Group 8Aa. Least reactive groupCurrent LectureI. Chapter 22: Chemistry of NonmetalsII. Classes of elementsa. MetalsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.i. Majority of tableii. Good conductors iii. Mostly positive oxidation numbersiv. Except for Hg, solids in their standard stateb. Metalloidsi. Properties of both metals and non-metalsii. Many are semiconductors (B, Si, Ge, As)1. Need a certain voltage to conduct electricityc. Nonmetalsi. Properties more diverse than metalsii. Poor conductorsiii. Both positive and negative oxidation numbersiv. H2, O2, N2, F2, Cl2, noble elements are gases at standard statev. Br2 is a liquid, all others are solidsIII. Properties of nonmetalsa. Only 17/114 are nonmetallic, life based on non-metallic elementsb. Negative oxidation states when combined with metals, can have positive oxidation states in bonding to other non-metalsc. Higher electronegativity’s than metalsd. Nonmetals oxides are acidic, combine with H2O to give oxy-acidsIV. Review of periodic propertiesa. Ionization Energyi. Minimum energy needed to remove an electron from a gaseous atom or ion; endothermicii. A  A+ + e-iii. Increases bottom to top, left to right b. Electron affinityi. Negative of enthalpy for electron gain by atom, smaller than IEii. Exothermic except for noble gasesiii. Ag + e-  A-c. Electronegativityi. Tendency of an atom to gain additional electron density while retaining itsoriginal electron densityii. Increases left to right, bottom to topd. Atomic radiii. Increases right to left, top to bottom, Noble gases largeii. Make atom negative, size increasesiii. Make atom positive, size decreasese. Periodic Trendsi. Within a group smaller atoms are more likely to form pi-bonds because they can get closer to other atomsV. Group 1A Hydrogena. Very common but unique; Makes upi. 75% of mass of universe (90% of atoms)ii. 11% of mass of oceansiii. About .15% of mass of earth’s crustiv. 0-.4% of mass of atmospherev. 9.5% of mass of human bodyb. Three Isotopesi. 1H protiumii. 2h deuteriumiii. 3H tritium: 12.3 year half-lifec. Does not really belong to any groupi. Only element with an unfilled 1s valence shell that can either gain or lose an electronii. Hydride (H-) very strong based. Hydrogen chemisty-3 types i. Ionic hydrides: Mg + H2  MgH2ii. Metallic hydrides: interstitial hydridesiii. Covalent hydrides: organic compounds are covalent hydridese. Properties of Hydrogeni. Very large bond enthalpiesii. Forms strong bonds with other elements; exothermiciii. It forms H-bonds with electronegative O, F, and N; strong intermolecular forcesf. Hydrogen Fuel cellsi. 2 H2 + 02  2 H20ii. Reaction is highly exothermiciii. Water is only productiv. Problem: how will we make the H2g. Hydrogen Productioni. Commercially produced from reaction of methane with steam at 1100 degrees Celsius or carbon and steamii. Its production from the electrolysis of water is not energy efficienth. Hydrogenationi. Addition of dihydrogen to multiple bonds (usually C double or triple bonded to C)VI. Noble Gases-Group 8Aa. Extremely stable and unreactiveb. Liquid He (boiling point 4.2 K) is used as a coolantc. Ne is used in electric signsd. Ar is used in light bulbs and as an insulating gas between panes in thermal windowse. Least reactive group (Higher IE)i. Called “inert” until 1962, with discovery of Xe+PtF6-ii. Many noble gas compounds include Xe and Kriii. He and Ne compounds unknowniv. Helium is 2nd most abundant element in