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Oxides.Classification. Preparation of oxides.
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INORGANIC SUBSTANCES
| SIMPLE | |||||
| Metals | Non-metals | COMPLEX | |||
| (Cu, Na, Al, Fe) | (S, Cl, C, As) |
| Oxides | Bases | Acids | Salts |
| Oxides - complex substances, consisting from two elements, one of which oxygen. | Bases - complex substances, in which atoms of metals bonded with one or several hydroxyls groups (according to electrolytic dissociation theory bases - complex substances, which under the dissociating in water solution are formed metal cations (or NH4+) and hydroxide anions OH-). | Acids - complex substances, consisting from hydrogen atoms and acid radical (according to electrolytic dissociation theory: acids - electrolytes, which under the dissociating form only H+ in the capacity of cations). | Salts - complex substances, which consist from atoms of metal and acid residuals. This the most multiple class of inorganic compounds. |
OXIDES
| Salts-forming | Non-salts forming |
| CO, NO, N2O |
| Basic | Amphoteric | Acid |
| It is a metal oxides in which metals display low oxidation number +1, +2 Na2O, MgO, CuO | (for metals with oxidation number +3, +4). As a hydrates it corresponding amphoteric hydroxide ZnO, Al2O3, Cr2O3, SnO2 | It is oxides of nonmetals and metals with oxidation number from +5 to +7. SO2, SO3, P2O5, Mn2O7, CrO3 |
Basic, amphoteric- corresponding bases; amphoteric, acid- corresponding acids. BASES Amphoteric Show also properties of weak acids. Alkalies(soluble in water) Hydroxides (insoluble in water)
ACIDS
| On composition | On hydrogen atoms number, which capable to substituted on metal |
| Oxygenless | Oxoacids (containing oxygen) | Monobasic (monoprotic) | Dibasic (diprotic) | Tribasic (triprotic) | |
| HCl, HBr, HI, H2S, HCN | HNO3, H2SO4, HClO4, H3PO4 | HCl, HNO3, HI, HClO3 (Those having one acidic proton) | H2SO4, H2SO3 H2SiO3 | H3PO4 |
On the basis of strengths or capacity to donate hydrogen ions, acids can be described as: Strong acids: Which are completely (100%) ionized in aqueous solutions. Hence at equilibrium, the concentration of acid molecules is very less and concentration of hydrogen ion reaches to maximum, e.g., HCl, HNO3, HClO4. Weak acids: They are only partially ionized in solution at equilibrium state. At equilibrium state, acid molecules are present and the concentration of hydrogen ion is less, e.g., HF, CH3COOH.
SALTS
| Medium | acidic | basic | Double | mixed | complex |
| In the time of dissociation give only metal cations (or NH4+) and anions of acid radical. Products of full substitution hydrogen atoms of acids to atoms of metals. Ex.: Na2SO4 | In the time of dissociation give only metal cations (or NH4+), hydrogen anions and anions of acid radical. Products of full substitution hydrogen atoms of multibasic acid to atoms of metal. Ex.: NaHCO3 | In the time of dissociation give only metal cations, hydroxyl anions and anions of acid radical. Products of incomplete substitution OH groups, corresponding bases to acid radicals Ex.: Mg(OH)Cl | In the time of dissociation gives two cations and one anion. Ex.: KAl(SO4)2 | Formed by means of one cation and two anions. Ex.: CaOCl2 | Contain complex cations or anions Ex.: [Ag(NH3)2]Br Na[Ag(CN)2] |
BINARY COMPOUNDS. A binary compound is a chemical compound that contains exactly two different elements. Examples of binary ionic compounds include calcium chloride (CaCl2), sodium fluoride (NaF), and magnesium oxide (MgO), while examples of a binary covalent compounds include water (H2O), and sulfur hexafluoride (SF6).Corresponding to the two limiting types of element, metal and nonmetal, there are three limiting types of binary compound: Metallic These are formed principally by the combination of a metal with a metal, and have the characteristics of a metal.Nonmetallic These are formed principally by the combination of a nonmetal with a nonmetal, and have the characteristics of a nonmetal.Salt-like These are formed principally by the combination of a metal with a nonmetal, and constitute a new class of material. In the formula for a binary compound, the element that attracts electrons less is usually written fi rst. The elements are assigned an electronegativity that refl ects their affi nity for electrons in chemical bonds. The elements that attract electrons most are said to have the highest electronegativities or to be the most electronegative. Fluorine, the most electronegative element, is assigned an electronegativity of 4.0, and the other elements have values relative to that of fl uorine. The elements that attract electrons least are said to have the lowest electronegativities or to be the most electropositive. Binary compounds naming rules. 1. The Cation (positive ion) is named first, the Anion second.2. Monoatomic Cations take the element nameNa+ → SodiumCa2+ → Calcium3. Monoatomic Anions take the elements name and ends with " -ide" Cl- → ChlorideNaCl → Sodium Chlorid Names of binary compounds.
| Anion | Compounds name | Example | Anion | Compounds name | Example |
| H- | hydride | NaH – sodium hydride | S2- | sulfide | Na2S – sodium sulfide |
| B3- | boride | Li3B – lithium boride | Cl- | chloride | LiCl – lithium chloride |
| C4- | carbide | Al4C3 – aluminum carbide | As3- | arsenide | AlAs – aluminum arsenide |
| N3- | nitride | Mg3N2 – magnesium nitride | Se2- | selenide | MgSe – magnesium selenide |
| O2- | oxyde | CaO – calcium oxyde | Br- | bromide | CaBr2 – calcium bromide |
| O22- | peroxyde | K2O2 – potassiun peroxide | Sb3- | antimonide | K3Sb – potassiun antimonide |
| O2- | superoxide (hyperoxide) | CsO2 – ceasium superoxide | Te2- | telluride | Cs2Te – ceasium telluride |
| O3- | ozonide | KO3 – potassium ozonide | I- | iodide | KI – potassium iodide |
| F- | fluoride | NaF – sodium fluoride | Bi3- | bismuthide | Na3Bi – sodium bismuthide |
| Si4- | silicide | Mg2Si – magnesium silicide | N3- | azide | AgN3 – silver azide |
| P3- | phosphide | Ca3P2 – calcium phosphide | C22- | acetylenide | Cu2C2 – copper acetylenide |
Binary covalent compounds are formed between two nonmetals. Although these compounds do not contain ions, they are named very similarly to binary ionic compounds. In the naming of binary covalent compounds, the following rules apply: 1. The fi rst element in the formula is named fi rst, using the full element name.2. The second element is named as if it were an anion.3. Prefi xes are used to denote the numbers of atoms present.4. The prefi x mono- is never used for naming the fi rst element. For example, CO is called carbon monoxide, not monocarbon monoxide.
Oxides.Classification. Preparation of oxides.
| Oxides - complex substances, consisting from two elements, one of which oxygen.Oxides: BASIC- It is a metal oxides in which metals display low oxidation number +1, +2. Na2O, MgO, CuO.AMPHOTERIC-(for metals with oxidation number +3, +4). As a hydrates it corresponding amphoteric hydroxide.ZnO, Al2O3, Cr2O3, SnO2.ACID- It is oxides of nonmetals and metals with oxidation number from +5 to +7.SO2, SO3, P2O5, Mn2O7, CrO3 1. Interaction of simple and complex substances with oxygen: 2Mg + O2 → 2MgO. 4P + 5O2 → 2P2O5.S + O2 → SO2.2CO + O2 → 2CO2.2CuS + 3O2 → 2CuO + 2SO2.CH4 + 2O2 → CO2 + 2H2O | |||
2. Decomposition some substances containing oxygen (bases, acids, salts) under the heating:
| tоС | |||
| Cu(OH)2 | → | CuO + H2O | |
| tоС | |||
| (CuOH)2CO3 | → | 2CuO + CO2 + H2O | |
| tоС | |||
| 2Pb(NO3)2 | → | 2PbO + 4NO2 + O2 | |
| H2SO4 (conc.) | |||
| 2HMnO4 | → | Mn2O7 + H2O | |