Potassium chloride sodium chloride (salt) magnesium chloride calcium chloride copper chloride zinc chloride barium chloride aluminum chloride
KCl sodium chloride magnesium chloride calcium chloride copper chloride zinc chloride barium chloride aluminum trichloride
Ferrous chloride ferric chloride silver chloride FeCl2 FeCl3 AgCl
(common acid)
Sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, hydrogen sulfide, hydrogen bromide and bicarbonate.
Sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, H2S, bicarbonate bromide.
(salt)
Copper sulfate, barium sulfate, calcium sulfate, potassium sulfate, magnesium sulfate, ferrous sulfate and ferric sulfate.
Copper sulfate, barium sulfate, calcium sulfate, potassium sulfate, magnesium sulfate, ferrous sulfate, ferric sulfate
Aluminum sulfate, sodium bisulfate, potassium bisulfate, sodium sulfite, sodium nitrate, potassium nitrate and silver nitrate.
Al2(SO4)3 nah so 4 khso 4 naso 3 nano 3 kno 3 agno 3
Magnesium nitrate, copper nitrate, calcium nitrate, sodium nitrite, sodium carbonate, calcium carbonate and magnesium carbonate.
Magnesium nitrate, copper nitrate, calcium nitrate, sodium nitrite, sodium carbonate, calcium carbonate, magnesium carbonate, potassium carbonate, potassium carbonate.
(common alkali)
Sodium hydroxide, calcium hydroxide, barium hydroxide, magnesium hydroxide, copper hydroxide, potassium hydroxide and aluminum hydroxide.
Sodium hydroxide Ca (OH) 2 Ba (OH) 2 mg (OH) 2 Cu (OH) 2 KOH Al (OH) 3 Fe (OH) 3 Fe (OH) 2 hydroxide.
Jingle of price
Monovalent elements of potassium, sodium, silver and hydrogen, divalent elements of calcium, magnesium, barium and zinc, trivalent elements of copper, iron, aluminum and gold, OH ion-1, (sulfate ion SO4, sulfite ion SO3, carbonate ion) -2, Cl ion and nitrate ion-/kloc-0. Remember these, and the chemical price will be OK ~
Precipitation:
Red-brown flocculent precipitate -Fe (OH) 3 light green precipitate -Fe (OH) 2 blue flocculent precipitate -Cu (OH) 2.
White precipitate -CaCO3, baco3, AgCl and BaSO4 (baso4 and AgCl are white precipitates insoluble in HNO3, and CaCO3 BaCO3 is white precipitate soluble in HNO3),
I. Acids, bases and salts
1, chemical properties of acid
(1) acid+metal salt+hydrogen
(2) Acid+metal oxide-salt+water
56. Reaction of iron oxide with dilute hydrochloric acid: Fe2O3+6HCl ==2FeCl3+3H2O.
57. The reaction of iron oxide with dilute sulfuric acid: Fe2O3+3H2SO4 == Fe2(SO4)3+3H2O.
58. The reaction of copper oxide with dilute hydrochloric acid: CuO+2HCl ==CuCl2+H2O.
59. The reaction between copper oxide and dilute sulfuric acid: CuO+H2SO4 == CuSO4+H2O.
(3) acid+alkali-salt+water (neutralization reaction)
60. Reaction between hydrochloric acid and caustic soda: HCl+NaOH == NaCl +H2O.
6 1. The reaction between hydrochloric acid and calcium hydroxide: 2HCl+Ca(OH)2 == CaCl2+2H2O.
62. Aluminum hydroxide drugs treat hyperacidity: 3HCl+Al(OH)3 == AlCl3+3H2O.
63. Reaction between sulfuric acid and caustic soda: H2SO4+2NaOH == Na2SO4+2H2O.
(4) acid+salt-another acid+another salt
64. marble reacts with dilute hydrochloric acid: CaCO3+2hcl = = CaCl2+H2O+CO2 =
65. Reaction of sodium carbonate with dilute hydrochloric acid: Na2CO3+2HCl = = 2NaCl+H2O+CO2 =
66. Sodium bicarbonate reacts with dilute hydrochloric acid: nahco3+HCl = = NaCl+H2O+CO2 =
67. The reaction between sulfuric acid and barium chloride solution: H2SO4+BaCl2 == BaSO4 ↓+ 2HCl.
2. Chemical properties of alkali
(1) alkali+nonmetallic oxide-salt+water
68. Caustic sodium will deteriorate when exposed to air: 2NaOH+CO2 == Na2CO3+H2O.
69. Caustic sodium absorbs sulfur dioxide gas: 2NaOH+SO2 == Na2SO3+H2O.
7 1. The slaked lime deteriorates in air: Ca(OH)2+CO2 == CaCO3 ↓+ H2O.
72. The slaked lime absorbs sulfur dioxide: Ca(OH)2+SO2 == CaSO3 ↓+ H2O.
(3) alkali+salt-another alkali+another salt
73. Calcium hydroxide and sodium carbonate: Ca(OH)2+Na2CO3 == CaCO3↓+ 2NaOH.
(3) Alkaline oxide+acid salt+water
37. The reaction of iron oxide with dilute hydrochloric acid: Fe2O3+6HCl === 2FeCl3+3H2O+3H2O.
38. Reaction of iron oxide with dilute sulfuric acid: Fe2O3+3H2SO4 = = Fe2 (SO4) 3+3H2O+3H2O.
39. Reaction of copper oxide with dilute hydrochloric acid: CuO+2hcl = = = CuCl2+H2O.
40. The reaction between copper oxide and dilute sulfuric acid: CuO+H2SO4 = = = CuSO4+H2O.
4 1. The reaction of magnesium oxide with dilute sulfuric acid: MgO+H2SO4 = = = MgSO4+H2O.
42. The reaction of calcium oxide with dilute hydrochloric acid: Cao+2 HCl = = = CaCl2+H2O.
(4) acidic oxide+alkaline salt+water
43. Caustic sodium will deteriorate when exposed to air: 2NaOH+CO2 ==== Na2CO3+H2O.
44. Caustic sodium absorbs sulfur dioxide gas: 2 NaOH+SO2 = = = Na2SO3+H2O.
45. Caustic sodium absorbs sulfur trioxide gas: 2NaOH+SO3 ==== Na2SO4+H2O.
46. The slaked lime deteriorates in the air: Ca (OH) 2+CO2 = = = CaCO3 ↓+H2O+H2O.
47. The slaked lime absorbs sulfur dioxide: ca (oh) 2+SO2 = = = caso3 ↓+H2O+H2O.
(5) acid+alkali-salt+water
48. Reaction of hydrochloric acid with caustic soda: HCl+NaOH = = = NaCl+H2O.
49. Reaction of hydrochloric acid and potassium hydroxide: HCl+KOH = = = KCl+H2O.
50. The reaction between hydrochloric acid and copper hydroxide: 2HCl+Cu (OH) 2 = = CuCl2+2H2O.
5 1. The reaction between hydrochloric acid and calcium hydroxide: 2hcl+Ca (OH) 2 = = CaCl2+2h2o.
52. The reaction between hydrochloric acid and iron hydroxide: 3HCl+Fe (OH) 3 = = = FeCl 3+3H2O.
53. Aluminum hydroxide for the treatment of hyperacidity: 3HCl+Al (OH) 3 = = = AlCl3+3H2O.
54. Reaction between sulfuric acid and caustic soda: H2SO4+2NaOH = = = Na2SO4+2H2O.
55. The reaction between sulfuric acid and potassium hydroxide: H2SO4+2koh = = = K2SO4+2h2o.
56. The reaction between sulfuric acid and copper hydroxide: H2SO4+Cu (OH) 2 = = CuSO4+2H2O.
57. The reaction between sulfuric acid and iron hydroxide: 3H2SO4+2Fe (OH) 3 = = Fe2 (SO4) 3+6H2O.
58. The reaction between nitric acid and caustic soda: nitric acid+sodium hydroxide = = = sodium nitrite+H2O H2O.
(6) acid+salt-another acid+another salt
59. marble reacts with dilute hydrochloric acid: CaCO3+2hcl = = CaCl2+H2O+CO2 =
60. Sodium carbonate reacts with dilute hydrochloric acid: Na2CO3+2HCl = = 2NaCl+H2O+CO2 =
6 1. Reaction of magnesium carbonate with dilute hydrochloric acid: MgCO3+2HCl = = MgCl2+H2O+CO2 =
62. Reaction between hydrochloric acid and silver nitrate solution: HCl+AgNO3 === AgCl↓+HNO3.
63. The reaction of sulfuric acid and sodium carbonate: Na2CO3+H2SO4 = = Na2SO4+H2O+CO2 =
64. The reaction between sulfuric acid and barium chloride solution: H2SO4+bacl2 = = = baso4 ↓+2hcl.
(7) alkali+salt-another alkali+another salt
65. Sodium hydroxide and copper sulfate: 2 NaOH+CuSO4 = = Cu (OH) 2 ↓+Na2SO4.
66. Sodium hydroxide and ferric chloride: 3 NaOH+FeCl 3 = = Fe (OH) 3 ↓+3 NaCl.
67. Sodium hydroxide and magnesium chloride: 2 NaOH+MgCl2 = = mg (OH) 2 ↓+2 NaCl.
68. Sodium hydroxide and copper chloride: 2 NaOH+CuCl2 = = Cu (OH) 2 ↓+2 NaCl.
69. Calcium hydroxide and sodium carbonate: Ca (OH) 2+Na2CO3 = = CaCO3 ↓+2NaOH.
(8) salt+salt-two new salts
70. Sodium chloride solution and silver nitrate solution: NaCl+AgNO3 = = = AgCl ↓+Nano3.
7 1. sodium sulfate and barium chloride: Na2SO4+bacl2 = = = baso4 ↓+2 NaCl.
1, basic reaction type:
Compound reaction: changeable; Decomposition reaction: one becomes more; Displacement reaction: first order for first order; Double decomposition reaction: exchange ions;
2 valence of common elements (positive valence):
Univalent potassium, sodium, hydrogen, silver, bivalent calcium, magnesium, barium and zinc, trivalent metal element aluminum; 157 variable valence chlorine, 245 nitrogen, 46 sulfur, 35 phosphorus, 24 carbon; One, two copper, two, three iron and two, four, six and seven manganese are special.
The study of acid, alkali and salt is the most important part in the chemistry study of senior three, which plays a decisive role in the senior high school entrance examination. However, it is difficult for students to master this part of knowledge because of its complicated content and certain depth. Here, I will briefly summarize the knowledge points that need to be mastered in this part:
First of all, the memory of color
There are many colored substances or solutions in this chapter. According to the law, it can be summarized as follows:
CuCuCuO Cu2 (OH) 2co3 CuSO4 solution
Red black green blue blue blue blue blue.
Fe2o 3 fe2o 4 Fe2+ solution Fe3+ solution Fe(OH)3
Silver white red black light green yellow red brown
Second, the memory of precipitation
Among the three grades, the most exposed sediments can be summarized as "six white", "one blue" and "one reddish brown"
"Bai Liu" CaCO _ 3ag2co _ 3baco _ 3baso _ 4agclmg (OH) 2
Soluble in dilute nitric acid, the gas produced is insoluble in dilute nitric acid, soluble in dilute nitric acid, and no gas is produced.
"A Blue" Cu(OH)2 "A Red Brown" Fe(OH)3
Third, the memory of some characteristic ions.
These characteristic ions play an important role in impurity removal or identification.
Example: If Na2CO3 mixed in NaCl is removed, please select the added reagent.
Thinking: The characteristic ion CO32- is related to some problems. If you want to remove CO32-, you should first think of H+
CO32- can react with H+ to generate water and carbon dioxide, so dilute hydrochloric acid can be used.
The equation is: Na2CO3+2HCl=2 NaCl+H2O+CO2.
In addition, CO32- can also react with Ca2+ to generate CaCO3 precipitate, so CaCl2 solution can also be selected.
Excluding CO32-, the equation is: Na2CO3+ CaCl2= CaCO3 +2 NaCl.
Therefore, the most commonly used characteristic ions are summarized as follows:
CO32- H+ Cl- Ag+ OH- Cu2+
Ba2+、Ca2+ SO42- Ba2+ Fe3+ Mg2+
The interaction between these ions can simplify many problems.
Fourth, the memory of the law of material reaction.
In the study of acid, alkali and salt, we can sum up eight laws of mutual reaction between substances:
1. metal+acid salt+hydrogen
2. Metal+salt-new metal+new salt substitution reaction
3. Acid+basic oxide-salt+water
4. Acid+alkali-salt+water
5. Acid+salt-new acid+new salt double decomposition reaction
6. Alkali+salt-new alkali+new salt
7. Salt+Salt-New Salt+New Salt'
8. Alkali+acid oxide-salt+water
The above rules play a very important role in our study of this part, because only by knowing the reaction rules between substances can we have a clear and complete idea to solve the problem.
Four, several common ion test
The test of Cl-,,,.
Experimental operation, experimental phenomenon, experimental conclusion, chemical equation
Cl- Take a small amount of sample in a test tube, and add AgNO3 solution and dilute HNO3 dropwise to generate a white precipitate insoluble in dilute nitric acid. The sample contains chloride ions.
Silver nitrate +KCl = silver chloride ↓+potassium nitrate
Take a small amount of sample in a test tube, and add Ba(NO3)2 solution and dilute HNO3 dropwise to produce a white precipitate insoluble in dilute nitric acid. The sample contains
Barium (nitric acid) 2+ sulfuric acid = barium sulfate ↓+nitric acid
Take a small amount of samples in the test tube, add dilute HCl dropwise, and introduce the generated gas into the clarified limewater to generate colorless gas, which makes the clarified limewater turbid. The sample contains
K2CO3+2HCl=2KCl+ CO2↑+H2O
Carbon dioxide+calcium hydroxide = calcium carbonate ↓+ H2O
◎ Selection of desiccant:
1, concentrated sulfuric acid can be dried: acidic gas (such as CO2, SO2, SO3, NO2, HCl,).
Neutral gas (such as H2, oxygen, N2, carbon monoxide)
Do not dry alkaline gas (such as NH3). ※
2. Sodium hydroxide solid, quicklime and alkaline lime can be dried: alkaline gas (such as NH3).
Neutral gas (such as H2, oxygen, N2, carbon monoxide)
Acid gases (such as CO2, SO2, SO3, NO2, HCl, etc. ) can't do it. ※
3. Anhydrous copper sulfate solid turns from white to blue when it meets water, which can test the existence of water and absorb water vapor.
Induction of knowledge of acid, alkali and salt in junior middle school chemistry
Induction of knowledge of acid, alkali and salt in junior middle school chemistry
First, the concept:
1, composition of acid-hydrogen ion+acid radical ion
2. Composition of alkali metal ions+hydroxide ions
3. Composition of salt-metal ion+acid ion
4. Double decomposition reaction-The reaction in which two compounds exchange components with each other to form two other compounds is called double decomposition reaction. AB+CD=AD+CB
5. Dilution method of concentrated sulfuric acid-Concentrated sulfuric acid must be slowly injected into the water along the wall of the device, and continuously stirred to make the generated heat spread rapidly. Never pour water into concentrated sulfuric acid.
6. Neutralization reaction-The reaction between acid and alkali to form salt and water is called neutralization reaction.
Second, memorize the valence formulas of common elements and atomic groups:
Potassium, sodium, silver, hydrogen, calcium, magnesium, barium, zinc, aluminum, silicon, nitrogen and phosphorus.
(negative valence) negative monovalent: fluorine, chlorine, bromine, iodine;
Negative divalent: oxygen and sulfur.
(Variable positive valence): copper, mercury, iron, carbon and sulfur.
(valence of atomic group)
Negative monovalent: hydroxyl (OH), nitrate (NO3), chlorate (ClO3), permanganate (MnO4);
Negative divalent: sulfate (SO4), carbonate (CO3), sulfite (SO3), manganate (MnO4);
Negative trivalent: phosphate (PO4);
Positive unit price: ammonium (NH4).
Third, remember the following reaction equations:
(1) The nature of the acid (1) reacts with the indicator, and the purple litmus test solution turns red, but the colorless phenolphthalein test solution does not change color.
(2) Acid+alkali = salt+water.
(3) Acid+some metal oxides = salt+water.
(4) Acid+active metal = salt+hydrogen.
(5) Acid+salt = new salt+new acid.
1, zinc reacts with dilute hydrochloric acid: Zn+2HCl = ZnCl2+H2 ↑ bubbles are generated, and zinc particles gradually decrease.
2. The reaction between zinc and dilute sulfuric acid: Zn+H2SO4 = ZnSO4+H2 =
3. Iron reacts with dilute hydrochloric acid: Fe+2HCl = FeCl2+H2 ↑ produces bubbles, and iron gradually decreases.
4. Iron reacts with dilute sulfuric acid: the solution of Fe+H2SO4 = FeSO4+H2 turns light green.
5. The rust reacts with dilute hydrochloric acid: Fe2O3 +6HCl = 2FeCl3+3H2O red rust gradually disappears.
6. Rust reacts with dilute sulfuric acid: Fe2O3+3H2SO4 = Fe2(SO4)3+3H2O solution turns yellow.
7. Copper oxide reacts with dilute hydrochloric acid: CuO+2HCl =CuCl2 +H2O black copper oxide gradually disappears.
8. Copper oxide reacts with dilute sulfuric acid: CuO+H2SO4 = CuSO4+H2O solution turns blue.
(2) Properties of alkali: (1) Alkali solution can turn purple litmus solution blue and colorless phenolphthalein solution red.
(2) Alkali+most nonmetallic oxides = salt+water
(3) Alkali+acid = salt+water
(4) alkali+some salt = another salt+another alkali
1. The reaction between sodium hydroxide and carbon dioxide: 2NaOH+CO2 = Na2CO3+H2O.
2. The reaction between sodium hydroxide and sulfur dioxide: 2NaOH+SO2 = Na2SO3+H2O.
3. The reaction between sodium hydroxide and sulfur trioxide: 2NaOH+SO3 = Na2SO4+H2O.