The reaction law of chemical metals in junior high school, and the reaction equation of chemical met

1. Metal + Acid = Salt + H2 Conditions: Pre-hydrogen metal, acid is hydrochloric acid or dilute sulfuric acid.

If the metal in the compound is +1 valence, then it is 2R+2HCl=2RCl+H2R=K,Na

If the metal is +2 valence in compound, then it is R+2HCl= Rcl2+H2 R=Zn,Fe,Mg

If the metal is +3 valence in compound, then it is 2r+3hcl=2rcl3+3h2 r=al

2. Elemental metal + salt (solution) — another metal + another salt.

Conditions: Elemental metals are pre-metal in salt (except potassium, calcium and sodium), and salt must be soluble in water.

fe+cuso4=feso4+cu

cu+2agno3=cu(no3)2+2ag

Methods for identifying the sequence of activity of the three metals.

There are generally two ways to do this. The principle is the same, according to the order table of metal activity, the metal in front can displace the metal in the back from its salt solution.

For example, iron, copper, and aluminum, we know from the order of metal activity that the order is aluminum, iron, copper.

So, there are the following methods:

1. Take iron element, aluminum chloride solution and copper sulfate solution. Iron is placed in aluminum chloride solution, there is no obvious phenomenon, indicating that iron is not as active as aluminum, and then iron is placed in copper sulfate solution, and a red substance appears on the surface, indicating that iron is more active than copper, combined, and the conclusion is: aluminum, iron, copper.

2. Take ferrous sulfate solution, aluminum and copper. When aluminum is placed in ferrous sulfate solution, the surface turns black, indicating that aluminum is more active than iron; Copper is placed in ferrous sulfate solution, and there is no obvious phenomenon, indicating that iron is more active than copper. Ibid.

3. This method is not a universal method. This question is available. Take the elemental and dilute hydrochloric acid of three metals. Put them in the same hydrochloric acid at the same time, with more bubbles in aluminum, less in iron, and no significant change in copper.

Metal + acid = salt + hydrogen (metal activity is stronger than hydrogen) Example: Fe + 2HCl = FeCl2 + H2 Zn + H2SO4 = ZnSO4 + H2

The only rule is the periodic table.

You go and look up the high school chapter on alkali metals.

Just know Le.

Junior high school chemistry has the participation of metalsChemical reactionsAn example of the equation is as follows:

Na+O2=Na2O2 (Condition: Ignition).

na+o2=2na2o

Na+S=Na2S (Condition: Heating).

Na+Cl2=2NaCl(Condition: Ignited).

na+2h2o=2naoh+h2↑

6. Mg+Cl2=MgCl2 (condition: ignition).

mg+N2=mg3N2 (condition: ignition).

8. Mg+2H2O=mg(OH)2+H2 (Condition: Heating).

9、mg+2hcl=mgcl2+h2↑

Mg+CO2=2mgo+C (condition: ignition).

al+6hcl=2alcl3+h2↑

AL+FE2O3=2FE+AL2O3 (condition: high temperature).

Fe+2O2=Fe3O4 (Condition: Ignite).

Fe + 3Cl2 = 2 FeCl3 (Condition: Ignition).

15. Fe+S=Fes (condition: heating).

16. Fe+I2=FEI2 (condition: heating).

17、fe+2hcl=fecl2+h2↑

18、fe+cuso4=feso4+cu

19、fecl3+fe=2fecl2

zn+2fecl3=3zncl2+2fe

Cu+S = Cu2S (Condition: Heating).

22. Fe+CuO=FeO+Cu (condition: high temperature).

Cu+O2=2cuO (Condition: Heating).

Chemical-** order of metal activity.

Magnesium burns in air: 2mg+o2=== ignited 2mgo iron burns in oxygen: 3fe + 2o2=== ignited fe3o4 copper heats in air:

2Cu + O2 === Heating 2Cuo Aluminum forms an oxide film in the air: 4Al + 3O2 ===2Al2O3 Mercury burns in oxygen: 2Hg + O2 === Ignites 2Hgo zinc and dilute sulfuric acid reaction:

Zn+H2SO4===ZNSO4+H2 Magnesium and dilute sulfuric acid reaction: MG+H2SO4===MGSO4+H2 Aluminum and dilute sulfuric acid reaction: 2AL+3H2SO4===AL2(SO4)3+3H2

Zinc and dilute hydrochloric acid reaction: Zn + 2HCl = = = ZnCl2 + H2 Magnesium and dilute hydrochloric acid anti or high sage: mg + 2HCl = = = MgCl2 + H2 Aluminum and dilute hydrochloric acid reaction:

2al+6hcl===2alcl3+3h2↑cuso4+fe===feso4+cu

cucl2+fe===fecl2+cu

cuso4+zn===znso4+cu

cucl2+zn===zncl2+cu

cuso4+al===also4+cu

cu+hg(no3)2===cu(no3)2+hg

The knowledge points about the chemical properties of the primary three metals are as follows:

Chemical properties of metalsReaction of metals with oxygenMetal + oxygen Metal oxidesActivity of metals: Mg>Al>Fe, Cu>au.

Aluminum reacts with oxygen at room temperature, and the cousin sensitive surface forms a dense film of alumina, which prevents further oxidation of aluminum. As a result, aluminum has very good corrosion resistance.

Reaction of Metals and Acids - Reaction of Metals with Dilute Hydrochloric Acid and Dilute Sulfuric Acid Chemical Equation Magnesium Bubbles are generated, and magnesium strips are gradually dissolved mg+H2SO4=MGso4+H2 mg+2HCl=mgCl2+H2

Zinc bubbles are generated, and zinc particles are gradually dissolved Zn+H2SO4=ZNSO4+H2 ZN+2HCl=ZnCl2+H2 Iron There are bubbles generated, and the iron gradually dissolves, and the solution changes from colorless to light green. Fe+H2SO4=FeSO4+H2 Fe+2HCl=FeCl2+H2 Copper Summary: The metal activity of magnesium, zinc, iron, and copper ranges from strong to weak.

Metal + acid compound + H2

The displacement reaction consists of the reaction of one element and one compound, and the reaction that produces another element and another compound is called the displacement reaction. (General form: a+bc ac+b).

The metal mobility requirement of the displacement reaction is to touch the width: to exchange the strong for the weak. Elemental metal compound solution (soluble in water) special case:

k+cuso4≠k2so4+cu2k+2h2o=2koh+h2↑

1) Elemental metals. Sour.

Salt + hydrogen (displacement reaction).

Pre-hydrogen metal, acid is hydrochloric acid or dilute sulfuric acid.

2) Elemental metals. Salt (solution).

Another metal.

Another salt. Elemental metals are pre-metal in salts (except potassium, calcium and sodium), and salts must be soluble in water.

3) Basic oxides. Sour.

Salt. Water. The acid is soluble in water. 4) Acidic oxides. Alkali.

Salt. Water. The alkali is soluble in water (not a metathesis reaction).

5) Acids. Alkali.

Salt. Water. At least one of acids and bases is soluble in water.

6) Acids. Salt.

Another acid. Another salt.

The insoluble salt of the junior high school is carbonate, and the acid is soluble and produces gas.

The reactants are soluble in water and form salts as precipitates.

7) Alkali. Salt.

Another alkali. Another salt.

The reactants must be soluble, and the ammonium salt is gaseous, and the non-ammonium salt must be precipitated.

8) Salt. Salt.

Two new salts. The reactants should be soluble, and the products should be precipitated.

Decomposition reaction of metallic elements.

High temperature calcined limestone (carbon dioxide industrial method) rotten mass closure: caCO3 == high or Wang temperature == cao + CO2

Heating potassium permanganate: 2kmNO4 == heating == K2mNO4 + mNO2 + O2

Heating basic copper carbonate: Cu2(OH)2CO3 == Heating == 2Cuo + H2O + CO2

Heating potassium chlorate (with a small amount of manganese dioxide dioxide): 2kClO3 ==2kCl + 3O2

In the third chemistry, the decomposition reaction of mercury oxidized Hgo produces the metal Hg and oxygen.

Chemical reaction, decomposition reaction, metathesis reaction, displacement reaction.