Knowledge of chemical properties of acids, in particular, their interaction with oxides, will serve good service when performing the most various tasks in chemistry. It will allow to solve settlement problems, to carry out a chain of transformations, to perform tasks of practical character and also will help on testing including on the USE.
It is required to you
- - sulfuric and hydrochloric acids;
- - oxides of potassium, calcium, aluminum;
- - test tubes.
Instruction
1. Acids represent complex substances which consist of atoms of hydrogen and the acid rest. Depending on amount of atoms of hydrogen of acid are classified on monobasic, bibasic and the three-main. In reactions of interaction of acids with oxides atoms of hydrogen are replaced on metal. Oxides can be acid, the main and amphoteric. To acid oxides there correspond acids, and the basic - the bases.
2. The main and amphoteric oxides can enter chemical reaction with acids therefore salt and water are formed. This type of reaction belongs to exchange reaction in which two complex substances exchange the components. Considering that the elements which are a part of oxide can have various valency, in the equations of reactions there will be different coefficients.
3. Example No. 1. Write two equations of reaction of interaction of hydrochloric and sulfuric acids with potassium oxide. In interaction of acids with potassium oxide which is the basic salt (chloride of potassium or sulfate of potassium) and water is formed. For this reaction monovalent metal the potassium which is a part of oxide.2HCl + K2O = 2KCl + H2OH2SO4 + K2O = K2SO4 + H2O is chosen
4. Example No. 2. Write two equations of reaction of interaction of hydrochloric and sulfuric acids with calcium oxide. In interaction of acid with oxide of calcium which is also the basic salt (chloride of calcium or sulfate of calcium) and water is formed. For this equation as a part of oxide bivalent metal is taken. 2HCl + CaO = CaCl2 + H2OH2SO4 + CaO = CaSO4 + H2O
5. Example No. 3. Write two equations of reaction of interaction of hydrochloric and sulfuric acids with aluminum oxide. In interaction of acid with oxide of aluminum which is amphoteric salt (chloride or sulfate of aluminum) and water is formed. For this equation trivalent metal as a part of oxide.6HCl + by Al2O3 = 2AlCl3 + 3H2O3H2SO4 + Al2O3 = Al2(SO4)3+ 6H2O is picked up