All the knowledge points of chemical metathesis reaction in junior high school

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Metathesis reaction is the reaction between the three substances of acid and alkali salts, but not all acid and alkali salts can occur metathesis reaction, the reaction is conditional, 1, there is gas generation 2, there is sedimentation generation 3, there is water generation As long as there is a condition in the reaction, you must get the solubility table of the substance when learning this part of the knowledge.

The chemical metathesis cave clearing reaction in junior high school is as follows:

1. Alkaline oxide + acid salt + H2O

fe2o3+6hcl==2fecl3+3h2o fe2o3+3h2so4==fe2(so4)3+3h2o

cuo+h2so4==cuso4+h2o zno+2hno3==zn(no3)3+h2o

2. Alkali + acid salt + H2O

cu(oh)2+2hcl==cucl2+2h2o cu(oh)2+h2so4==cuso4+2h2o

naoh+hcl==nacl+h2o 2naoh+h2so4==na2so4+2h2o

naoh+hno3==nano3+h2o mg(oh)2+2hno3==mg(no3)2+2h2o

ba(oh)2+h2so4==baso4↓+2h2o

3. Acid + salt New salt + new acid.

caco3+2hcl==cacl2+h2o+co2↑ na2co3+2hcl==2nacl+h2o+co2↑

hcl+agno3==agcl↓+hno3 h2so4+bacl2==baso4↓+2hcl

ba(no3)2+h2so4==baso4↓+2hno3 nahco3+hcl==nacl+h2o+co2↑

Metathesis reaction:

Metathesis reaction is a type of chemical reaction, which is composed of two chemical compounds under certain conditions, after the chemical reaction fails, it will generate a new chemical reaction of two chemical compounds, and the metathesis reaction is one of the most basic and important four types of chemical reaction in chemical learning and research.

The three conditions under which metathesis reactions can occur (i.e., precipitation or gas or water in the product) have effectively guided scientific experiments and production practices for a long time. It has been shown through practice that a substance or resalt can be precipitated in the reaction due to temperature difference or concentration, and metathesis reaction can also occur.

Metathesis reaction:

31. Marble and dilute hydrochloric acid (laboratory CO2): CaCO3 + 2HCl = CaCl2 + H2O + CO2

32. Sodium hydroxide and copper sulfate: 2NaOH + CuSO4 = Cu (OH) 2 + Na2SO4

33. Sodium carbonate and hydrochloric acid (fire extinguisher principle): Na2CO3 + 2HCl = 2NaCl + H2O + CO2

34. Potassium carbonate (plant ash) and hydrochloric acid: K2CO3 + 2HCl = 2KCl + H2O + CO2

35. Hydrochloric acid and sodium hydroxide (neutralization reaction): HCl+NaOH=NaCl+H2O

36. Sulfuric acid and sodium hydroxide solution: H2SO4 + 2NaOH = Na2SO4 + 2H2O

37. Sulfuric acid and barium chloride solution: H2SO4 + BACl2 = BASO4 + 2HCl

38. Hydrochloric acid and silver nitrate solution: HCl + AGNO3 = AGCL (Baizhi rent shout) + HNO3

39. Sodium hydroxide and ferric chloride solution: 3NaOH + FeCl3 = Fe (OH) 3 (reddish brown) + 3NaCl

40. Barium carbonate and dilute nitric acid: BAC3 + 2Hno3 = BA (NO3)2 + CO2 + H2O

41. Sodium sulfate and barium chloride: Na2SO4 + BACl2 = BaSO4 + 2NaCl

42. Sodium chloride and silver nitrate: NaCl + Agno3 = AgCl + Nano3

43. Sodium carbonate and lime water: Na2CO3 + Ca(OH)2=CaCO3 +2NaOH

44. Aluminum hydroxide and hydrochloric acid Mengye: Al(OH)3+3HCl=AlCl3 +3H2O

45. Ammonium nitrate and sodium hydroxide: NH4NO3 + NaOH = = nano3 + H2O + NH3

46. Iron hydroxide and sulfuric acid: 2Fe(OH)3+3H2SO4=Fe2(SO4)3

47. Hydrochloric acid rust removal: Fe2O3 + 6HCl = 2FeCl3 + 3H2O

48. Copper oxide and sulfur-type cleavage acid: CuO + H2SO4 = CuSO4 + H2O

Introduction to the equations of metathesis reactions in junior high school:

1. Marble and dilute salt transport acid (laboratory CO2): CaCO3 + 2HCl = CAC12 + H2O + CO21.

2. Sodium hydroxide and copper sulfate: 2NaOH+CuSO4=Cu(OH)21+Na2SO4.

3. Sodium carbonate and hydrochloric acid (fire extinguisher principle): Na2CO3 + 2HCl = 2NaCl + H2O + CO21.

4. Potassium carbonate (plant ash) and hydrochloric acid: K2CO3 + 2HCl = 2KCI + H2O + CO21.

5. Hydrochloric acid and sodium hydroxide (neutralization reaction): HCl+NaOH=NaCl+H2O.

6. Sulfur code and sodium hydroxide solution: H2SO4 + 2NaOH = Na2SO4 + 2H20.

7. Sulfuric acid and barium chloride solution: H2SO4 + BACl2 = BaSO4 + 2HCI.

8. Hydrochloric acid and silver nitrate solution delayed solution: HCl + AGNO3 = AGCIL (white) + HNO3.

9. Sodium hydroxide and ferric chloride solution: 3NaOH + FeC13 = Fe (OH) 3 (reddish brown) + 3NaCl.

10. Barium carbonate and dilute nitric acid: BAC3+2HNO3=BA(NO3)2+CO21+H20.

In junior high school, acid-base reactions produce salt and water...Take it as you like.

Decomposition reaction: CaCO3=CaO+CO2 calcined limestone.

Decomposition reaction: 2H2O=2H2+O2 electrolyzed water.

And many more, in the book, summarize it yourself.

NaCl+AgNO3=Nano3+AGCl Na2CO3+CaCl2=2NaCl+CaCO3 BaCl2+K2SO4=2KCl+BaSo4 BaCl2+Na2CO3=2NaCl+BaCO3 Na2CO3+2NH4Cl=2NaCl+2NH3 +CO2 +H2O is not very typical, because it is basically precipitation here, and the common salt precipitation is only silver chloride, Barium sulfate and most carbonates. The latter one is more demanding, and it is better not to write it in the exam.

The answer is supplemented. It is not important to memorize these formulas, it is important to memorize the solubility table, so that you can judge whether a metathesis reaction has occurred.

1. Alkaline oxide + acid salt + H2O

fe2o3+6hcl==2fecl3+3h2o fe2o3+3h2so4==fe2(so4)3+3h2o

cuo+h2so4==cuso4+h2o zno+2hno3==zn(no3)3+h2o

2. Alkali + acid salt + H2O

cu(oh)2+2hcl==cucl2+2h2o cu(oh)2+h2so4==cuso4+2h2o

naoh+hcl==nacl+h2o 2naoh+h2so4==na2so4+2h2o

naoh+hno3==nano3+h2o mg(oh)2+2hno3==mg(no3)2+2h2o

ba(oh)2+h2so4==baso4↓+2h2o

3. Acid + salt New salt + new acid.

caco3+2hcl==cacl2+h2o+co2↑ na2co3+2hcl==2nacl+h2o+co2↑

hcl+agno3==agcl↓+hno3 h2so4+bacl2==baso4↓+2hcl

ba(no3)2+h2so4==baso4↓+2hno3 nahco3+hcl==nacl+h2o+co2↑

4. Salt 1 salt 2 new salt 1 new salt 2

kcl+agno3==agcl↓+kno3 nacl+agno3==agcl↓+nano3

na2so4+bacl2==baso4↓+2nacl bacl2+2agno3==2agcl↓+ba(no3)2

5. Saline alkali new salt new alkali.

cuso4+2naoh==cu(oh)2↓+na2so4 fecl3+3naoh==fe(oh)3↓+3nacl

ca(oh)2+na2co3==caco3↓+2naoh naoh+nh4cl==nacl+nh3↑+h2o

5. Other reactions:

1. Carbon dioxide is passed into the clarified lime water

CO2 + Ca(OH)2 ==CaCO3 + H20 phenomenon: clarified lime water becomes turbid.

CO2 can be tested with clarified lime water, and lime water can also be tested with CO2).

Metathesis reaction:

1. Alkaline oxide + acid salt + H2O

fe2o3+6hcl==2fecl3+3h2o fe2o3+3h2so4==fe2(so4)3+3h2o

cuo+h2so4==cuso4+h2o zno+2hno3==zn(no3)3+h2o

2. Alkali + acid salt + H2O

cu(oh)2+2hcl==cucl2+2h2o cu(oh)2+h2so4==cuso4+2h2o

naoh+hcl==nacl+h2o 2naoh+h2so4==na2so4+2h2o

naoh+hno3==nano3+h2o mg(oh)2+2hno3==mg(no3)2+2h2o

ba(oh)2+h2so4==baso4↓+2h2o

3. Acid + salt New salt + new acid.

caco3+2hcl==cacl2+h2o+co2↑ na2co3+2hcl==2nacl+h2o+co2↑

hcl+agno3==agcl↓+hno3 h2so4+bacl2==baso4↓+2hcl

ba(no3)2+h2so4==baso4↓+2hno3

nahco3+hcl==nacl+h2o+co2↑

4. Salt 1 salt 2 new salt 1 new salt 2

kcl+agno3==agcl↓+kno3 nacl+agno3==agcl↓+nano3

na2so4+bacl2==baso4↓+2nacl bacl2+2agno3==2agcl↓+ba(no3)2

cacl2+na2co3==caco3↓+2nacl

5. Saline alkali new salt new alkali.

cuso4+2naoh==cu(oh)2↓+na2so4 fecl3+3naoh==fe(oh)3↓+3nacl

ca(oh)2+na2co3==caco3↓+2naoh naoh+nh4cl==nacl+nh3↑+h2o

mgcl2+2naoh==mg(oh)2↓+2nacl fe2(so4)3+3ba(oh)2=3baso4↓+2fe(oh)3↓

Metathesis reaction: A reaction in which two compounds exchange components with each other to form two other compounds.

Judgment conditions: There is precipitation in the product, water is formed, or gas is formed.

The reactions between acids and alkalis belong to metathesis reactions, mainly of the following types:

1) Acids. Metal oxide = = salt + water.

For example: Cuo + H2SO4 = = CuSO4 + H2O(2) acid + salt = = another acid + another salt (carbonate and acid react to form carbon dioxide) such as: Na2CO3

2hcl=2nacl+h2o

CO2 3) Acid + Base = = Salt + Water.

4) Alkali salt Another alkali Another salt.

For example: 2NaOH+CuSO4=Cu(OH)2+Na2SO4 (to generate a blue precipitate).

na2co3+

ca(oh)2

caco3↓+2

Naoh5) salt salt another salt another salt.

For example: Na2CO3+CaCl2=CaCO3

2nacl