Seek the summary of knowledge points of chemistry and life like the first multiple-choice question of chemistry in college entrance examination ~

25. The composition of gastric acid is hydrochloric acid (HCl). Common antacids include sodium bicarbonate, calcium carbonate, magnesium carbonate, aluminum hydroxide and magnesium hydroxide. The chemical equation and ionic equation of its reaction with gastric acid are respectively:

Sodium bicarbonate+hydrochloric acid = sodium chloride+H2O+carbon dioxide Sodium bicarbonate-+hydrogen+= H2O+carbon dioxide

CaCO3+2 HCl = CaCl 2+H2O+CO2 CaCO3+2H+= Ca2 ++ H2O+CO2

Magnesium carbonate+hydrochloric acid = magnesium chloride+H2O+carbon dioxide Magnesium carbonate+2H+ = magnesium++H2O+carbon dioxide.

Al(OH)3+3 HCl = ALC L3+3H2O Al(OH)3+3H+= Al3 ++ 3H2O

Magnesium hydroxide +2 hydrochloric acid = magnesium chloride+2H2O magnesium hydroxide+2H+ = magnesium ion++2H2O

26. Ephedrine belongs to natural Chinese herbal medicine and is a stimulant strictly prohibited by the International Olympic Committee.

27.r stands for prescription drugs and OTC stands for over-the-counter drugs.

28. An alloy is a substance with metallic characteristics formed by fusing two or more metals (or metal and nonmetal). Compared with metals with various compositions, it has the characteristics of high hardness and low melting point.

29. The corrosion of metals can be divided into chemical corrosion and electrochemical corrosion, and the corrosion in humid environment belongs to electrochemical corrosion.

30. Pig iron and steel are two kinds of iron alloys with different carbon contents.

The negative reaction of electrochemical corrosion of 3 1. iron is Fe-2e-=Fe2+

32. The methods to prevent metal corrosion are: ① changing its internal structure (such as making stainless steel); (2) Add protective film (such as painting, oiling and plastic film) on the metal surface. ); ③ Connect more active metal (such as zinc plating on Fe surface) to the protected metal.

33. The main raw materials for making ordinary glass are soda ash (Na2CO3), limestone (CaCO3) and timely (SiO2). The components of ordinary glass are Na2SiO3, CaS iO3 and SiO2, and the main component is SiO2.

34. The main raw material for making ceramics is clay.

35. The raw materials for making cement are limestone and clay. Its main components are tricalcium silicate, dicalcium silicate and tricalcium aluminate. Cement is hydraulic, so it should be protected from moisture when stored.

36. The main component of optical fiber is SiO2, referred to as optical fiber.

Generally speaking, the three major synthetic materials refer to plastics, synthetic fibers and synthetic rubber.

38. Plastics are divided into thermoplastics and thermosetting plastics.

39. Normal rain is acidic, with a pH of around 5.6. Acid rain refers to precipitation with pH less than 5.6, which is mainly converted from acid gases such as SO2 and NO2.

SO2→h2so 4 SO2+H2O h2so 3 2h2so 3+O2 = 2h2so 4

NO→ Nitrate 2NO+O2 = 2NO2 3NO+H2O = 2HNO3+NO.

40. chlorofluorocarbons will destroy the ozone layer because they decompose chlorine atoms under ultraviolet irradiation and play a catalytic role in changing ozone into oxygen.

4 1.SO2 mainly comes from coal combustion, and NO2 mainly comes from automobile exhaust.

42. The main sources of greenhouse gas carbon dioxide are burning fossil fuels and deforestation. Leading to a sharp decrease in forest area.

43. The chemical equation for desulfurization of coal with limestone is 2co3+2so2+O2 = = 2caso4+2co2.

44. The catalytic converter is installed in the automobile exhaust system, and its chemical equation is 2co+2no 2co2+N2.

45. The binder of decoration materials contains formaldehyde, and natural marble contains radioactive element radon.

46. Elements such as N and P in domestic sewage will cause eutrophication of water bodies.

47. Alum [kal (SO4) 2. 12h2o] is a commonly used coagulant.

The principle of water purification is: Al3 ++ 3H+2O Al(OH)3 (colloid) +3H+

48. Treating acidic and alkaline wastewater with neutralization method.

49. Sewage containing heavy metal ions is mainly treated by precipitation method.

"White pollution" refers to the pollution caused by waste plastic products.

5 1. The logo displayed on the right side of a trash can means: recyclable garbage 1. The molecular formula of glucose is C6H 12O6. Glucose is a monosaccharide and cannot be hydrolyzed.

2. The test method of glucose is: (1) reacting with silver ammonia solution under alkaline and heating conditions to precipitate silver. This reaction is called the silver mirror reaction of glucose. (2) Under alkaline and heating conditions, it reacts with newly generated copper oxide to generate brick red precipitate (Cu2O).

3. The chemical equation of glucose providing energy for human body: C6h12o6+6o2co2+6H2O.

4. Starch is a polysaccharide with the molecular formula of (C6H 10O5)n, and the final product of its hydrolysis is glucose. Its chemical equation is: (C6H 10O5)n (starch) +NH2NC 12O6 (glucose).

5. Starch inspection: Iodized water (I2) turns blue.

6. The component of cotton and linen is cellulose, and its molecular formula is (C6H10O5) N. It is a kind of polysaccharide, and the final product of its hydrolysis is glucose.

7. The main component of oil is higher fatty glyceride, which provides the most calories per unit mass.

8. Oils and fats are hydrolyzed under acidic or enzymatic conditions to generate higher fatty acids and glycerol; Hydrolysis under alkaline conditions produces higher fatty acid salts and glycerol, and alkaline hydrolysis of oil is also called saponification reaction.

9. The general formula of amino acids is that the functional groups contained in the molecule are amino (-—NH2) and carboxyl (-—COOH).

10. Wool and silk belong to protein. A simple way to identify silk: burning has the smell of burnt feathers [source: subject network ZXXK]

1 1. The salting-out of protein refers to the process that protein condenses and precipitates from protein solution after adding some concentrated inorganic light metal salts (such as NaCl, (NH4)2SO4 and Na2SO4) to protein solution. Salting out is a reversible process. This reaction can be used to separate and purify protein.

12. Copper salt and barium salt can denature protein. Drink plenty of milk to detoxify after eating heavy metal ions by mistake.

13. There are 8 kinds of amino acids in human body that cannot be synthesized by themselves, which are called essential amino acids.

Vitamins are divided into fat-soluble vitamins (such as vitamins A, D, E and K) and water-soluble vitamins (such as vitamins C and B) according to their solubility.

15. Vitamin C, also known as ascorbic acid, is a water-soluble vitamin with acidity and reducibility, which is widely found in fresh fruits and green vegetables.

16. Iodine is an essential trace element for human body and is called "intellectual element". About half of them are concentrated in the thyroid gland. Among foods, kelp, marine fish and other seafood contain the most iodine. Potassium iodate (KIO3) is added to iodized salt.

17. Iron is one of the most essential trace elements for human body. Iron deficiency can lead to iron deficiency anemia. Foods containing more iron include animal viscera, whole blood, meat, fish and eggs.

18. The acidity and alkalinity of food is classified according to the acidity and alkalinity of food metabolites.

Non-metallic elements such as carbon, nitrogen, sulfur and phosphorus contained in acidic foods.

Such as meat, eggs, fish and other substances rich in protein.

Metal elements such as potassium, sodium, calcium and magnesium in alkaline food.

Such as vegetables, fruits, etc.

19. Under normal circumstances, the pH value of human blood is always kept in the weak alkaline range (7.35~7.45). For a long time, due to the low intake of vegetables and fruits, the urine of Chinese residents is generally acidic.

20. No coloring agent can be added to baby food.

2 1. Commonly used flavoring agents are salt, vinegar, monosodium glutamate, sugar, etc.

22. Commonly used preservatives are sodium benzoate, potassium sorbate and sodium nitrite. Sodium nitrite is not only a preservative, antioxidant, but also a food colorant.

23. Aspirin has antipyretic and analgesic effects.

24. Penicillin is an important antibiotic, namely an anti-inflammatory drug. Skin allergy test (skin test) should be carried out before use to prevent allergic reaction.