College entrance examination chemistry questions often test knowledge points.

As a special form of chemistry course in senior high school, what are the common knowledge points of college entrance examination? Next, I'll tidy it up for you. Let's have a look.

: carbonate

1. The existence, common name or use of some carbonates.

Marble, limestone, eggshells, shells and stalactites-CaCO3; Soda, soda-Na2CO3;

Baking soda -nahco 3 can be used for food foaming, and ammonium bicarbonate -nh4hco 3 nitrogen fertilizer can be used for treating hyperacidity;

The main component of plant ash-K2CO3 potash fertilizer; The main components of boiler scale-calcium carbonate and magnesium hydroxide;

Raw materials for making ordinary glass-limestone, soda ash and seasonable; Raw materials for making cement-limestone and clay

2. Normal and acid salts of carbonic acid

1, mutual transformation: experimental phenomenon of calcium carbonate and calcium bicarbonate transformation; Formation of limestone caves and stalactites

Conversion of sodium carbonate and sodium bicarbonate The reaction between sodium carbonate solution and hydrochloric acid is not as intense as that of sodium bicarbonate. Removing sodium carbonate impurities from the sodium bicarbonate solution; Removing sodium bicarbonate impurities from sodium carbonate; Why should sodium bicarbonate solution be used instead of sodium carbonate solution to remove hydrogen chloride impurities in carbon dioxide? When carbon dioxide gas is introduced into saturated sodium carbonate solution, sodium bicarbonate precipitates: ① water is consumed; ② The solubility of sodium carbonate is greater than that of sodium bicarbonate; ③ The quality of sodium bicarbonate produced is greater than that of sodium carbonate in the original solution.

2.* * * Homology: Both of them can react with acids stronger than carbonic acid to generate carbon dioxide gas. Inspection of carbonate

3. Stability comparison: normal salt is more stable than acid salt: acid

Such as hclo

Experimental phenomenon of sodium bicarbonate heating: experimental phenomenon of heating calcium bicarbonate solution

4. Solubility comparison: Generally speaking, the solubility of acidic salts is stronger than that of normal salts such as CaHCO 32 >; Calcium carbonate, counterexample: sodium bicarbonate

5. Similarities and differences of some reactions between sodium bicarbonate and sodium carbonate.

(1), all common carbonates-carbon dioxide generated by reaction with hydrochloric acid should be familiar with the comparison of acid consumption and gas production under various conditions.

(2) using lime water or barium hydroxide solution to generate white precipitate;

(3) Sodium bicarbonate can react with alkali such as sodium hydroxide, but sodium carbonate can't;

(4) The solution of sodium carbonate and calcium chloride or barium chloride is easy to generate carbonate precipitation, while the solution of sodium bicarbonate and dilute salt is not easy to generate carbonate precipitation.

: hydrogen chloride and hydrochloric acid

1, concentrated hydrochloric acid is oxidized by manganese dioxide in the laboratory to generate chlorine gas.

2. Hydrochloric acid and sodium chloride react with silver nitrate solution respectively; Inspection of hydrochloric acid and chloride solution; Testing of bromide and iodide

3, the reaction of hydrochloric acid and alkali

4, the reaction of hydrochloric acid and alkaline oxides

5. Hydrochloric acid reacts with active metals such as zinc.

6. Hydrochloric acid reacts with weak acid salts such as sodium carbonate and ferrous sulfide.

7, hydrochloric acid and sodium phenolate solution reaction.

8, dilute hydrochloric acid and bleaching powder reaction

9. Addition reaction of hydrogen chloride and ethylene

10, PVC was produced by the addition reaction of hydrogen chloride and acetylene.

1 1. The reaction between bleaching powder and carbon dioxide in the air shows that carbonic acid is more acidic than HClO.

Comparison of acidity of 12, HF, HCl, HBr and HI HF is a weak acid, wHIle HCl, HBr and hi are strong acids, and the acidity increases in turn.

13, what is the material used for artificial rainfall? Dry ice, AgI

The composition of some common substances

1. Effective component calcium chloride of bleaching powder, ineffective component calcium chloride and pyrite ferrous sulfide; 3. black powder c, KNO3, s;

4. Alum kalso4212h2o; 5. Alumni FeSO47H2O6. Blue alum and bile alum CuSO45H2O7. Barite barium sulfate

8. Soda ash and soda Na2CO39 baking soda NaHCO3 10 quicklime CaO 1 1 hydrated lime.

2; 12. limestone and marble CaCO3 13 aqua regia concentrated nitric acid concentrated hydrochloric acid1∶ 3; 14. Timely. Crystalline silica; 15. corundum Al2O3

16. Boiler scale calcium carbonate and magnesium hydroxide; 17. Iron red, hematite Fe2O3 18. Magnetic iron oxide, magnetite Fe3O4 19. pencil lead materials-clay and graphite;

20. Coal-a complex mixture of organic matter and inorganic matter; 2 1. petroleum-a complex mixture mainly composed of alkanes, cycloalkanes and aromatic hydrocarbons.

22. Biogas, natural gas CH423 alkali lime CaO, NaOH24 chloroform CHCl324, calcium carbide CaC225, glycerol-glycerol;

26. Carbonic acid-phenol; 27. Formalin-formaldehyde solution; 28. Sodium soap salts of higher fatty acids

Elemental sulfur and its compounds

The nonmetallic reaction of elemental sulfur is weaker than that of halogen, oxygen and nitrogen.

1. Sulfur reacts with oxygen to produce only sulfur dioxide, but not sulfur trioxide.

2. Sulfur reacts with hydrogen by heating.

3. Sulfur reacts with copper to form a+1 valence copper compound, namely cuprous sulfide.

4. Sulfur reacts with iron to generate +2 valence iron compound, namely ferrous sulfide.

5. Sulfur reacts with mercury at room temperature, and the mercury beads that cannot be collected after HgS scattering should be sprinkled with sulfur powder to prevent mercury vapor poisoning.

7. Sulfur reacts with strong alkali solution to generate sulfide, and sulfur attached to sulfite test tube can be cleaned with CS2 or used.

Wash 3s+6 NaOH = 2n2s+Na2SO3+3H2O with NaOH solution.

The reaction of sulfur dioxide or sulfurous acid is a weakly oxidizing, strongly reducing and acidic oxide.

1. Hydrogen sulfide oxide

2. Catalyst for the production of industrial sulfuric acid by oxygen oxidation: Sulfur dioxide in the air is absorbed by oxygen under the action of some suspended dust and sunlight.

Oxidized into sulfur trioxide, dissolved in rain and snow to become acidic precipitation.

3 SO2+Cl2+2h2o is oxidized by halogen = = H2SO4+2hcl

React with water

5. Reaction with basic oxides

React with alkali

7. Colorless substances are synthesized by bleaching and organic coloring. The generated colorless substances are not very stable and will change color after heating or after a period of time.

Overview of properties and uses of trisulfuric acid

1. Strong acidity

1, reacting with alkali

2, react with alkaline oxide to remove rust; Preparation of copper sulfate and other salts

3. React with weak acid salt to prepare some weak acid or acid salt.

4. React with active metal to generate hydrogen.

2. The water absorption of concentrated sulfuric acid is used as a gas desiccant;

3. Dehydration of concentrated sulfuric acid carbonizes wood strips, paper pieces and sucrose. Dehydration of ethanol to ethylene

4. Strong oxidizing property of concentrated sulfuric acid

1, passivation of metals such as iron and aluminum;

2, reacting with inert metal copper and heating.

3. React with charcoal and heat.

4. Blacken the reaction mixture when producing ethylene.

5. Making volatile acids with high boiling points.

1, hydrogen chloride gas production

2. Nitric acid Nitric acid is soluble, and concentrated sulfuric acid is used.

Sulfuric acid is generally not used in the laboratory to produce carbon dioxide, because another reactant is usually massive limestone, and the calcium sulfate generated by the reaction is soluble.

Small easy to wrap on the surface hindered the further reaction.

6. It is often used as a catalyst in organic reactions.

1, ethylene is used as catalyst and dehydrating agent, and a large amount of concentrated sulfuric acid is used. The volume ratio of ethanol concentrated sulfuric acid is 1∶3.

2. sulfuricacid used as catalyst for nitration and water absorption, and concentrated sulfuric acid was used.

3. Sulfuric acid is used as catalyst and water absorbent in esterification reaction, and concentrated sulfuric acid is used.

4, ester hydrolysis with sulfuric acid as catalyst, with dilute sulfuric acid.

5, sugar hydrolysis Note: When detecting hydrolysate, first add alkali to neutralize sulfuric acid.

7. Industrial preparation of sulfuric acid

"43": three stages, three devices, three reactions and three principles: increasing contact area, heat exchange and counter-current thinking: how to choose the production conditions of industrial sulfuric acid? The reason and catalyst of adopting normal pressure for temperature and pressure; Why should the gas from the combustion furnace be purified before entering the contact chamber?