Basic Chemistry II Vladimíra Kvasnicová

Exercise Add names of the elements: N Na K Ca Mg Mn Ag Cd Hg Sb nitrogen sodium potassium calcium magnesium manganese silver cadmium mercury antimony

The figure is found at (September 2007)

Inorganic Compounds Make groups of compounds: Na 2 O, HCl, CO 2, Na 2 O 2, Ca(OH) 2, KClO, HCN, HNO 2, H 2 S, H 2 O 2, BaO 2, PbO 2, H 2 SO 3, KOH, MgSO 4, NaF, NH 4 HCO 3, HI, Al(OH) 3, HIO 4, CdS, MgO 2, NaH 2 PO 4 ? oxides hydroxides peroxides acids salts

Inorganic Compounds Make groups of compounds: Na 2 O, HCl, CO 2, Na 2 O 2, Ca(OH) 2, KClO, HCN, HNO 2, H 2 S, H 2 O 2, BaO 2, PbO 2, H 2 SO 3, KOH, MgSO 4, NaF, NH 4 HCO 3, HI, Al(OH) 3, HIO 4, CdS, MgO 2, NaH 2 PO 4 ? oxides hydroxides peroxides acids salts

Inorganic Compounds Oxidesanion: O -II acid-forming: nonmetal / oxygen  use multiple prefixes (mono, di, tri,...) base-forming: metal / oxygen  use sufixes –ous / -ic or (oxidation state) amphoteric MnO 2, N 2 O, BaO, CO, K 2 O, SO 2, FeO, Cu 2 O, CaO

Inorganic Compounds Peroxidesanion: O 2 -2  O -I s 1 elements (hydrogen and alkali metals): M 2 O 2 s 2 elements (alkali earth metals): MO 2 sodium peroxidemagnesium peroxide barium peroxidepotassium peroxide hydrogen peroxidelithium peroxide

Inorganic Compounds Hydroxidesanion: (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, NH 4 OH, 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, H 2 S, HCN (in aqueous solutions) anion: -ide monoprotic / diprotic acids

Inorganic Compounds Acidscation: H + 2) oxoacids  the highest oxidative stateper ic acid  higher (or only) oxidative state -ic acid  lower oxidative state -ous acid  the lowest oxidative statehypo-...-ous acid anion: -ic acid → -ate -ous acid → -ite

Inorganic Compounds The most important oxoacids: H 2 CO 3 carbonic acid H 2 SiO 3 silicic acid H 2 CrO 4 chromic acid H 3 BO 3 boric acid H 3 PO 4 phosphoric acid H 2 SO 3 sulfurous acid H 2 SO 4 sulfuric acid HNO 2 nitrous acid HNO 3 nitric acid → carbonate → silicate → chromate → borate → phosphate → sulfite → sulfate → nitrite → nitrate

Inorganic Compounds The most important oxoacids: HClO hypochlorous acid HClO 2 chlorous acid HClO 3 chloric acid HClO 4 perchloric acid (or Br, I) HMnO 4 permanganic acid H 2 S 2 O 2 thiosulfurous acid H 2 S 2 O 3 thiosulfuric acid → hypochlorite → chlorite → chlorate → perchlorate → permanganate → thiosulfite → thiosulfate

Keep in mind the rules: 1.names of compounds are derived from the names of cations, anions and polyatomic ions: cation anion (NaCl = sodium chloride) 2.all binary compounds end in –ide CaO, H 2 O 2, NaCl, HF(g), ZnS 3.binary compounds composed of two nonmetals: Greek prefixes SO 2, N 2 O 5, CO

Keep in mind the rules: 4.binary compounds composed of a metal ion with fixed or variable oxidation numbers and nonmetal ion: no Greek prefixes a) -ous / -ic suffix system b) Stock system (prefered) CuCl 2, CuCl, Fe 2 O 3, FeO

Keep in mind the rules: 5.ternary compounds:  hydrogen cation H + (= acid)  or metal cation (= salt or hydroxide) (fixed or variable oxidation number)  and a polyatomic anion (e.g. SO 4 2- or OH 1- ) H 2 SO 4 Na 2 SO 4 NaOH Total charge of a molecule = 0

Inorganic Nomenclature Call the compounds: Na 2 O, HCl, CO 2, Na 2 O 2, Ca(OH) 2, KClO, HCN, HNO 2, H 2 S, H 2 O 2, BaO 2, PbO 2, H 2 SO 3, KOH, MgSO 4, NaF, NH 4 HCO 3, HI, Al(OH) 3, HIO 4, CdS, MgO 2, NaH 2 PO 4

Chemical reactions = chemical changes stoichiometry = the reactants combine in simple whole- number ratios (see stoichiometric coefficients: a, b, c, d) a A + b B → c C + d D the single arrow ( → ) is used for an irreversible reaction double arrows (  ) are used for reversible reactions chemical equilibrium = a state of a reversible chemical reaction in which the concentrations of reactatnts and products are not changing with time ie the rates of both the forward and back reactions are equal

Chemical reactions equilibrium constant (K) describes the ratio of concentrations of products and reactants in the equilibrium a A + b B  c C + d D K = [C] c [D] d / [A] a [B] b K is constant for given reaction and fixed temperature the definition of K is called Guldberg-Waage´s law (= law of chemical equilibrium)

Chemical reactions a chemical reaction is described by a chemical equation the equation is balanced if substance amount of each element is the same on both sides of a chemical equation  each element must be balanced in the order: metal – nonmetal – hydrogen - oxygen Conservation law (Law of conservation of mass / energy) = the total magnitude of mass (or energy or charge) remain unchanged even though there may be exchanges of that property between components of the system (the sum of masses of reactants equals to the sum of masses of products)

Chemical reactions NEUTRALIZATION = acid-base reactions H 2 SO NaOH → Na 2 SO H 2 O acid + base → salt + water PRECIPITATION NaCl + AgNO 3 → AgCl (s) + NaNO 3 → insoluble product = precipitate is formed REDOX reactions = oxidative-reduction reactions → oxidation states of elements are changed !!!

Chemical reactions oxidative-reduction reactions = REDOX reactions → oxidation states of elements are changed !!! two changes:  one element is oxidized (its ox. state raises)  other element is reduced (its ox. state lowers) 2 HCl + Zn → ZnCl 2 + H 2 Zn 0 → Zn +II zinc is oxidized (0 → +II) H +I → H 0 hydrogen is reduced (+I → 0)

Important terms: reactants / products stoichiometric coefficients substance amount relative atomic / molecular mass molar mass density concentration (molar, percent)

Exercise – add formulas sodium sulfite potassium phosphate ammonium hydrogen phosphate lithium dihydrogen phosphate calcium hydrogen carbonate silver sulfide zinc sulfate potassium permanganate sodium hypobromite barium nitrate hydrargyric chloride

Exercise – add formulas sodium tetraborate decahydrate potassium aluminium sulfate sodium aluminium sulfate dodecahydrate ammonium carbonate calcium sulfate hemihydrate (hemi = ½) zinc sulfate heptahydrate potassium dichromate potassium magnesium fluoride ammonium magnesium phosphate led(II) chloride fluoride cupric biscarbonate difluoride (bis = twice)