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Anonymous users2024-02-111) Elemental metal + acid - salt + hydrogen (displacement reaction).
1. Zinc and dilute sulfuric acid reaction: Zn + H2SO4 === ZNSO4 + H2
2. Magnesium and dilute sulfuric acid reaction: mg + H2SO4 === MGSO4 + H2
3. Reaction of aluminum and dilute sulfuric acid: 2AL + 3H2SO4 === AL2(SO4)3 + 3H2
4. Zinc and dilute hydrochloric acid reaction: Zn + 2HCl === ZNCL2 + H2
5. Magnesium and dilute hydrochloric acid reaction: mg+ 2HCl === mgCl2 + H2
6. Reaction of aluminum and dilute hydrochloric acid: 2AL + 6HCl === 2ALCL3 + 3H2
Phenomenon: Bubbles are generated.
7. Reaction of iron and dilute hydrochloric acid: Fe + 2HCl === FeCl2 + H2
8. Reaction of iron and dilute sulfuric acid: Fe + H2SO4 === FeSO4 + H2
Phenomenon: Bubbles are generated, and the solution changes from colorless to light green.
2) Elemental metal + salt (solution) - another metal + another salt.
9. Iron reacts with copper sulfate: Fe+CuSO4==Cu+FeSO4
Phenomenon: The surface of the iron bar is covered with a layer of red substance, and the solution changes from blue to light green.
10. Put the zinc tablets into copper sulfate solution: CuSO4+ZN==ZNSO4+CU
Phenomenon: The surface of the zinc sheet is covered with a layer of red substance, and the solution turns from blue to colorless.
11. Put the copper sheet into silver nitrate solution: 2AGnO3+Cu==Cu(NO3)2+2AG
Phenomenon: The surface of the copper sheet is covered with a layer of silvery-white substance, and the solution changes from colorless to blue.
Reaction of aluminum and copper sulfate solution: 2AL +3 CuSO4 === AL2(SO4)3 + 3Cu (The surface of the aluminum wire is covered with a layer of red.)
Solid, the color of the solution changes from blue to colorless. ）
3) Metal oxides, charcoal or hydrogen, metals, carbon dioxide or water.
12. Coke reduced iron oxide: 3C + 2Fe2O3 = high temperature = 4Fe + 3CO2
13. Charcoal reduction copper oxide: C + 2Cuo = high temperature = 2Cu + CO2
Phenomenon: The black powder does not turn red, and the clarified lime water becomes turbid.
14. Hydrogen reduction copper oxide: H2 + Cuo = = Cu + H2O
Phenomenon: The black powder turns red, and water beads form on the inner wall of the test tube.
15. Magnesium and copper oxide reaction: mg+cuo ====Cu+mgo
16. Hydrogen reacts with iron oxide: Fe2O3 + 3H2 = high temperature = 2Fe + 3H2O
17. Water vapor passes through the hot carbon layer: H2O + C = High temperature = H2 + CO
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Anonymous users2024-02-10Chemistry mantra:
1. In order to remember the structure of the periodic table, there is such a slip: eighteen longitudinal rows and seven horizontal rows, one hundred and four tables contain seven main, seven vices, zero and eight, three short, three long and one incomplete.
2. In the periodic law, the relationship between the parity of the main valence of an element and the parity of its ordinal number:"The price is odd and the order is strange, and the price is even and the order can be remembered as homophonic: marry (price) chicken (odd) with chicken, marry dog (even) with dog.
3. The writing method of isomers is the formula of carbon chain shortening: the main chain is long to short, the branch chain is whole to scattered, the position center is to the edge, and the arrangement is between neighbors.
4. The top 10 elements in the earth's crust: formula: raising a girl to stick the lid of the pot, which family does not have green vegetables (oxy-silicon, aluminum, iron, calcium, sodium, potassium, magnesium, hydrogen, titanium).
5. Solubility formula: potassium, sodium, ammonium nitrate soluble, hydrochloric acid in addition to mercury, sulfuric acid insoluble with barium lead, carbonic acid is mostly insoluble, and dissolved alkali is only potassium, sodium and barium ammonia.
6. Common valency formulas in junior high school: monovalent hydrochloride, potassium, sodium silver, divalent oxygen, calcium, barium, magnesium, zinc, trialuminum, tetrasilicon, pentavalent phosphorus, copper and mercury, bivalent are the most common, 23 iron, 24 carbon, 246 sulfur are all available, and 235 valent nitrogen accounts for all.
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Anonymous users2024-02-09We are all memorized step by step,,, if we have a formula, we won't work hard back then, and we will memorize chemistry textbooks from morning to night, really! Our chemistry teacher is very bt, and I can't go back to eat if I don't have it back...
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Anonymous users2024-02-08There's no formula for this kind of thing, but you can figure out how the reaction works, and finally trim it, and a lot of reactions can be compared.
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Anonymous users2024-02-07I haven't heard of a formula for chemical equations.
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Anonymous users2024-02-06Salt formula: potassium and sodium ammonia melt quickly, sulfate sinks barium silver calcium, chloride sinks mercurous silver, and carbon silicon phosphorus brine sinks.
Chemical valence formula: monovalent hydrochloride, potassium, sodium silver, divalent barium oxygen, calcium, magnesium, zinc, trialuminum, copper, phosphorus, phosphorus, 23iron, 246 carbon, 246 sulfur are complete, and copper mercury bivalent is the most common.
Metal activity formula: potassium, calcium, sodium, magnesium, aluminum, zinc, iron, tin, lead, copper, mercury, silver, platinum. k ca na mg al zn fe sn pb (h) cu hg ag pt au
Hope it helps! ^_o(∩_o~！！
Speaking of which, if you are not interested, you must not be able to learn quickly and remember well. If you are interested, you don't need to memorize it at all, memorize it, and you will know what the test is at a glance. Speaking of my experience, I didn't know anything about chemistry at first, but one day, I previewed the textbook in advance, and I felt that the class was very relaxed. >>>More
Guo Degang: As soon as I came, I took over a good job and built a chimney of more than 70 meters! >>>More
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