Lecture September 12

Transcription

1 Lecture September 12 Goal for today: Chapter 3 Part II HW and Quiz due September 19th - through Section 3.6 p naming compounds Don t worry about hydrates Skip 3.10 for now Will NOT do Sec Organic Compounds at all!! 1

2 Ions with Multiple Charges hydrogen helium 1 2 H WebElements: the periodic table on the world-wide web Transition Metals (7) Key: (2) lithium beryllium element name boron carbon nitrogen oxygen fluorine neon 3 4 atomic number Li Be symbol B C N O F Ne 6.941(2) (3) 2003 atomic weight (mean relative mass) (7) (8) (7) (3) (5) (6) sodium magnesium aluminium silicon phosphorus sulfur chlorine argon Na Mg Al Si P S Cl Ar (2) (6) (2) (3) (2) (5) (2) (1) potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr (1) (4) (8) (1) (1) (6) (9) (2) (9) (4) (3) 65.38(2) (1) 72.64(1) (2) 78.96(3) (1) (2) rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe (3) 87.62(1) (2) (2) (2) 95.96(2) [98] (2) (2) (1) (2) (8) (3) (7) (1) (3) (3) (6) caesium barium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon Cs Ba Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn (2) (7) (1) (2) (1) (1) (1) (3) (3) (2) (2) (2) (2) 207.2(1) (2) [209] [210] [222] francium radium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium ununbium ununtrium ununquadium ununpentium ununhexium ununseptium ununoctium Fr Ra Lr Rf Db Sg Bh Hs Mt Ds Rg Uub Uut Uuq Uup Uuh Uus Uuo [223] [226] [262] [267] [268] [271] [272] [270] [276] [281] [280] [285] [284] [289] [288] [293] [294] He lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium Lanthanoids La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb (2) (1) (2) (3) [145] (3) (1) (3) (2) (1) (2) (3) (2) (5) actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium Actinoids Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No [227] (1) (2) (3) [237] [244] [243] [247] [247] [251] [252] [257] [258] [259] Element symbols and names: symbols, names, and spellings are recommended by IUPAC ( Names are not yet proposed for the elements beyond those used here are IUPAC s temporary systematic names (Pure & Appl. Chem., 1979, 51, ). In the USA and some other countries, the spellings aluminum and cesium are normal while in the UK and elsewhere the usual spelling is sulphur. Atomic weights (mean relative masses): Apart from the heaviest elements, these are IUPAC 2007 values (Pure & Appl. Chem., 2007, in press). Elements with values given in brackets have no stable nuclides and are represented by integer values for the longest-lived isotope known at the time writing. The elements thorium, protactinium, and uranium have characteristic terrestrial abundances and these are the values quoted. The last significant figure of each value is considered reliable to ±1 except where a larger uncertainty is given in parentheses. Periodic table organisation: for a justification of the positions of the elements La, Ac, Lu, and Lr in the WebElements periodic table see W.B. Jensen, The positions of lanthanum (actinium) and lutetium (lawrencium) in the periodic table, J. Chem. Ed., 1982, 59, Group labels: the numeric system (1 18) used here is the current IUPAC convention. For a discussion of this and other common systems see: W.C. Fernelius and W.H. Powell, Confusion in the periodic table of the elements, J. Chem. Ed., 1982, 59, Dr Mark J Winter [WebElements Ltd and University of Sheffield]. All rights reserved. For updates to this table see Version date: 21 September

3 Ions with Multiple Charges Know Table 3.2 for ions with fixed charges Transition metals with fixed charges Sc 3+ Zn 2+ Ag + Assume all others can change - as given in Table 3.4 Add the (II), (III), (IV) to indicate the charge of the metal ion - otherwise name the same as for fixed charges 3

4 Some Examples Chlorides with fixed charge cations: ScCl3 ZnCl2 AgCl scandium chloride zinc chloride silver chloride Chlorides with variable charge cations: FeCl2 FeCl3 iron(ii) chloride iron(iii) chloride 4

5 Polyatomic Anions Know Table 3.5 Examples: Nitrate ion NO3 - NH4 ammonium ion Hydroxide ion OH - AgNO3 NaNO3 NH4NO3 Ca(OH)2 Fe(OH)2 silver nitrate sodium nitrate ammonium nitrate calcium hydroxide iron(ii) hydroxide 5

6 Molecular Compounds prefix name of first element prefix base name + ide see p. 93 same as for ionics Usually compounds combining non-metals N and O N2O dinitrogen monoxide NO2 nitrogen dioxide N2O5 dinitrogen pentaoxide 6

7 Naming Acids H is the first element - must be in AQUEOUS SOLUTION (aq) Binary Acids hydro HCl(g) hydrogen chloride base name acid + ic HCl(aq) hydrochloric acid Oxyacids: ate anion base name of oxyanion + ic acid ous anion base name of oxyanion + ous acid 7

8 Examples of Oxyacids acetate ion Must Know TABLE 3.5!! ACID (aqueous solution) C2H3O2 - HC2H3O2(aq) acetic acid nitrate ion NO3 - HNO3(aq) nitric acid nitrite ion NO2 - HNO2(aq) nitrous acid (more on board - polyprotic acids) 8

9 Molecular Weight (Formula Mass) Molecular weight = sum of the atomic weights of the constituent atoms calcium oxide CaO calcium oxide = = g Ca O This is the mass of 1 mole of CaO - molar mass, molecular weight, formula mass 9

10 Molar Mass and Percent Composition (by mass) CaO % Ca = (40.08/56.08) x 100 = 71.47% % O = (16.00/56.08) x 100 = 28.53% Total = % # moles = mass/molar mass # molecules = moles x x

11 Example (I) How many CaCO3 molecules are in g? Molar mass CaCO3 = (16.00) = # molecules = g (1 mol/ g) (6.022 x molecules/ mol) = Answer: x molecules CaCO3 What is the percentage (by mass) of Ca in CaCO3? Mass of Ca / mass of CaCO3 = 40.08/ Answer: % by mass How many Ca atoms are in g of CaCO3? # Ca atoms = [( x.40046)/40.078] x 6.022x10 23 Answer: x atoms of Ca 11

12 Quiz of the Day Give the formula or name for the following ionic compounds: a) aluminum bromide AlBr3 b) Cr2O3 chromium (III) oxide 12