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Classification of inorganic substances.
INORGANIC SUBSTANCES
OXIDES
Basic, amphoteric- corresponding bases; amphoteric, acid- corresponding acids. BASES
ACIDS
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
Сурак 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: o Metallic These are formed principally by the combination of a metal with a metal, and have the characteristics of a metal. o Nonmetallic These are formed principally by the combination of a nonmetal with a nonmetal, and have the characteristics of a nonmetal. o 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 name Na+ → Sodium Ca2+ → Calcium 3. Monoatomic Anions take the elements name and ends with " -ide" Cl- → Chloride NaCl → Sodium Chloride Li3N → Lithium Nitride 5. Oxides and bases. Preparation and chemical properties.Preparation of oxides. 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:
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