All the chemistry equations in junior high school are here to help

I think it's better to read more books, books are the foundation, so that the chemical equations are not much use, and it is simple to understand and look at these equations after reading the books.

The third year of the chemical equation encyclopediaEquation for the Law of Conservation of Mass:

1.Magnesium burns in air: 2mg + O2 ignites 2mgo

2.Iron and copper sulfate solution reaction: Fe + CuSO4 ==FeSO4 + Cu

3.Reduction of copper oxide by hydrogen: H2 + Cuo heating Cu + H2O

4.Magnesium reduced copper oxide: mg + cuo heated cu + mgo

Equation for the reaction of metals with oxygen:

1.Magnesium burns in air: 2mg + O2 ignites 2mgo

2.Iron burns in oxygen: 3Fe + 2O2 ignites Fe3O4

3.Copper is heated in air: 2cu + o2 heats 2cuo

4.Aluminum forms an oxide film in the air: 4Al + 3O2 = 2Al2O3

Alkali + non-metallic oxide – salt + water

1.Caustic soda deteriorates when exposed to air: 2NaOH + CO2 ==Na2CO3 + H2O

2.Caustic soda absorbs sulfur dioxide gas: 2NaOH + SO2 ==Na2SO3 + H2O

3.Caustic soda absorbs sulfur trioxide gas: 2NaOH + SO3 ==Na2SO4 + H2O

4.Slaked lime deteriorates in air: Ca(OH)2 + CO2 ==CaCO3 + H2O

5.Slaked lime absorbs sulfur dioxide: Ca(OH)2 + SO2 ==CaSO3 + H2O

Junior high school chemical substance testing(1) Gas inspection

1. Oxygen: Put the wooden strip with sparks in the bottle, if the wooden strip is rekindled, it is oxygen.

2. Hydrogen: ignite the gas at the glass tip, cover a dry and cold small beaker, observe whether there are water droplets on the wall of the cup, pour clear lime water into the beaker, if it is not turbid, it is hydrogen.

3. Carbon dioxide: pass into the clarified lime water, if it becomes turbid, it is carbon dioxide.

4. Ammonia: moist purple-red litmus test paper, if the test paper turns blue, it is ammonia.

5. Water vapor: through anhydrous copper sulfate, if the white solid turns blue, it contains water vapor.

(2) Ion inspection.

1. Hydrogen ions: add purple litmus test solution dropwise and add zinc grains.

2. Hydroxide ion: phenolphthalein test solution, copper sulfate solution.

3. Carbonate ions: dilute hydrochloric acid and clarified lime water.

4. Chloride ions: silver nitrate solution and dilute nitric acid, if white precipitate is produced, it is chloride ions.

5. Sulfate ions: barium nitrate solution and dilute nitric acid are added dropwise with dilute hydrochloric acid and then dropped with barium chloride.