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Basic Chemistry I. Vladimíra Kvasnicová. Composition of Matter. organic / inorganic compound = a substance formed by chemical reaction; it consists of elements in fixed proportions
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Basic Chemistry I Vladimíra Kvasnicová
Composition of Matter • organic / inorganic • compound = a substance formed by chemical reaction;it consists of elements in fixed proportions • element = a substance that cannot be decomposed into simpler substances; it consists of atoms with a same number of protons (number of neutrons may vary) --------------------------------------------------------------- • atom = the smallest part of an element that can exist chemically • molecule = the smallest part of a chemical compoundthat can take part in chemical reaction
Composition of Matter structure of atom • nucleus: protons (p+) + neutrons (n0) • „cloud“ of electrons (e-) • mass number A (= nucleon number) • proton number Z (= atomic number) • neutron number N • electroneutrality • nuclide • isotopes
inorganic mater oxygen (O) 50% silicon (Si) 25% aluminium (Al) 7% iron (Fe) 5% calcium (Ca) 3% 90% sodium (Na) potassium (K) magnesium (Mg) hydrogen (H) titanium (Ti) 0,6% organic mater „compounds of carbon“ C, O, H, N carbon (C) oxygen (O) hydrogen (H) nitrogen (N) phosphorus (P) sulfur (S) Composition of Matter • air, blood plasma
Distinguish • isotopes = atoms having the same protonnumber but different mass number(isotopes of carbon: 12C, 13C, 14C) • element= a substance composed of atoms havingthe same protonnumber(element consists of various isotopes) • nuclide = a substance composed of atoms havingthe same proton and mass numbers(substance containing only 12C = nuclide called carbon „12“) • atom / molecule / ion(monoatomic, polyatomic - binary, ternary)
Exercise • nuclide: AZX • make groups of: a) isotopes b) the same elements c) the same nuclides
Exercise • nuclide: AZX • make groups of: a) isotopes: iodine, uranium b) elements: iodine, uranium, radon c) the same nuclides: 3, 8 Calculate number of neutrons of 127I n0 = 74
Memorize symbols and names of elements use flash cards
The figure is found at http://www.corrosionsource.com/handbook/periodic/periodic_table.gif(September 2007)
Composition of Matter structure of atom – arrangement of electrons • four quantum numbers orbital = a region of space in which an electron is most likely to be found • principal shells → energy • subshells → shape of orbitals • degenerate orbitals → space orientation • spin (rotation) of electrons
s px py pz Shapes of orbitals
dyz dxy dzx dx2–y2 dz2 Shapes of orbitals
Composition of Matter structure of atom – arrangement of electrons • Pauli´s exclusion principle= no two electrons in the atom can have the same set of quantum numbers • Hund´s rule= electron will not enter an orbital containing another electron if an empty orbital of the same energy is available
The figure is found at http://www.corrosionsource.com/handbook/periodic/periodic_table.gif(September 2007)
Composition of Matter structure of atom – arrangement of electrons • ground / excitated state • valence electrons • radicals • electronegativity = a measure of the ability of an atom in a molecule to draw bonding electrons to itself • chemical bonds
the arrow showes increase of electronegativity The figure is found at http://www.corrosionsource.com/handbook/periodic/periodic_table.gif(September 2007)
Inorganic Compounds Oxides anion: O-II • acid-forming: nonmetal / oxygen • use multiple prefixes (mono, di, tri,...) • base-forming: metal / oxygen • use sufixes –ous / -ic or (oxidation state) • amphoteric MnO2, N2O, BaO, CO, K2O, SO2, FeO, Cu2O, CaO
Inorganic Compounds Peroxides anion: O2-2 O-I • s1 elements (hydrogen and alkali metals): M2O2 • s2 elements (alkali earth metals): MO2 sodium peroxide magnesium peroxide barium peroxide potassium peroxide hydrogen peroxide lithium peroxide
Inorganic Compounds Hydroxides anion: (OH)-1 • basic properties (pH > 7) • strong or weak hydroxides • metal / hydroxide anion • use sufixes –ous / -ic or (oxidation state) • ammonium / hydroxide anion NaOH, LiOH, NH4OH, Fe(OH)3, Cu(OH)2, Ca(OH)2
Inorganic Compounds Acidscation: H+(pH < 7) 1) oxygen free acids hydro-...................-ic acid HF, HCl, HBr, HI, H2S, HCN (in aqueous solutions) anion:-ide • monoprotic / diprotic acids
Inorganic Compounds Acidscation: H+ 2) oxoacids • the highest oxidative state per-.....-ic acid • higher (or only) oxidative state -ic acid • lower oxidative state -ous acid • the lowest oxidative state hypo-...-ous acid anion: -ic acid → -ate -ous acid→ -ite
Inorganic Compounds Salts are formed by neutralization: acid + hydroxide → salt + water cation: metal or NH4+ derived from the hydroxide(= cation of the hydroxide) anion:oxygen-free or polyatomic anionderived from the acid (= anion of the acid)
Inorganic Compounds Make groups of compounds: Na2O, HCl, CO2, Na2O2, Ca(OH)2, KClO, HCN, HNO2, H2S, H2O2, BaO2, PbO2, H2SO3, KOH, MgSO4, NaF, NH4HCO3, HI, Al(OH)3, HIO4, CdS, MgO2, NaH2PO4 ? oxides hydroxides peroxides acids salts