If the acid, one or all hydrogen atoms substituted by another cation, such a chemical substance called salt.Metal or ammonium group in a molecule always has a positive oxidation state and are called cation.Acid residue is called an anion.All salts formed with metals that belong to Group Ia of the periodic table, are soluble.With regard to salts formed IIa group metals, the solubility varies.There
medium, if all of the hydrogen molecule in the polybasic acid is substituted by another cation, as well as acid salts, if, along with metal cations or ammonium presence of positively charged hydrogen.As an example, the average salt can cause:
- magnesium sulfate MgSO4;
- aluminum sulphate Al2 (SO4) 3;
- ammonium phosphate (NH4) 3PO4;
- sodium carbonate Na2CO3.
dissociation medium salts occurs on the positive metal cations and anions negative acid residue.Name of the average salt is derived from the acid and the cation of its generators.
Acid salts are formed by partial substitution of hydrogen on a metal or ammonium group.Thus, they are composed of metal, and the hydrogen acid residue.Their formation is possible only for the polybasic acids.Examples of such compounds:
- sodium bicarbonate NaHCO3;
- sodium dihydrogen phosphate NaH2PO4;
- sodium hydrogen phosphate Na2HPO4;
- potassium hydrogen sulphate KHSO4.The title
present their prefix "hydroxy" (if one unsubstituted hydrogen cation) or "dihydro" (if there are two unsubstituted hydrogen cations).
In aqueous solutions, the acid addition salts are dissociated to negative anions as anions, as well as two types of positive cations (metal ions and hydrogen): NaHSO4 ↔ Na + + H + + SO4ˉ ˉ.Hydrolysis acidic salts formed with strong acids, an aqueous solution having a pH of less than 7, hence the name of the salts.Hydrolysis of acid salts derived from weak acids (e.g., hydrogen), the solution is neutral or alkaline, i.e. a pH of at least 7.
If average salts may be prepared by reacting the metal with an acid, and other means, the receivingacid salts based on interaction with an excess:
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polybasic acid with an average salt.The obtained sodium sulfate: + H2SO4 → Na2SO4 2NaHSO4, water-soluble ammonium hydrogenphosphate (NH4) 2HPO4: H3PO4 + 2NH3 → (NH4) 2HPO4 or calcium hydrogen: CO2 + H2O + CaCO3 → Ca (HCO3) 2;
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polybasic acid with alkali.For example, based on receipt of dihydrogen is barium reaction equation: 2H3PO4 + Ba (OH) 2 → Ba (H2PO4) 2 + 2H2O.Influencing acid alkali salts, since they are the products of incomplete neutralization can again receive an average salt;
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acidic oxide with an alkali, so get calcium hydrogen: 2CO2 + Ca (OH) 2 → Ca (HCO3) 2.
known that hydrocarbons do not exist for the elements standing in the periodic table to the right of the group IIa, and solid hydrocarbons obtained only for a group of Ia.
salts are widely used in various industries, but some general areas of use there, as are all individually.The use of this type of salt depends on the properties of chemical compounds and is determined by economic expediency.
example, hydrogen, ammonium (NH4) 2HPO4 used as phosphorus-ammonium compound fertilizer in agriculture.Furthermore, this compound is used in fire-fighting: fire protection they handle different structures.Also, (NH4) 2HPO4 are used as an additive in the manufacture of certain grades of cigarettes.Sodium hydrosulfite
NaHSO3 used for the bleaching of different materials and photos.
Calcium hydrosulfite Ca (HSO3) 2 is a valuable raw material for the production of pulp from timber.
bisulfite, which are acid salts of sulfurous acid H2SO3, are part of the drug epinephrine, and are also used in molecular biology.
potassium hydrogen sulphate KHSO4 and NaHSO4 sodium used as a flux in the non-ferrous metallurgy.
Sodium bicarbonate NaHCO3 - the substance, the most famous of the acid salts.It is produced in Sterlitamak (the company "Soda") of the technical specifications set out in the GOST 2156-76.Sodium bicarbonate is used in the food, chemical and pharmaceutical industries, in medicine and in the home.
