What are the classifications of acid and alkali salts
Acid and alkali salts belong to three major categories of substances
HCL acid
NAOH base
Classification of NACL hydrochloric acid and alkali salts
Base definition: a compound in which the anions generated during ionization are all hydroxide ions.
Generally, alkali = metal + OH
Acid definition: A compound in which all cations generated during ionization are hydrogen ions.
Generally, acid = H + CL/SO3/SO4/CO3/NO3/PO4. There are only a few types of acids, which are easy to remember.
Oxide definition: A compound composed of two elements, one of which is O, is an oxide. It is easy to judge according to the definition. Note that it must be composed of only two elements, one of which is O.
The definition of salt: a compound composed of metal ions and acid ions. The acid radical is what is left after H is removed by acid. Not an acid, not an alkali, not an oxide, usually a salt.
Name Molecular Formula Solubility State
Nitric acid HNO3 solution
Hydrochloric acid HCl solution
Sulfuric acid H2SO4 solution (high concentration, Similar to oil)
Carbonic acid H2CO3 solution, easily volatile
Ammonia NH3·H2O solution, easily volatile
Ammonia salt solution
Potassium salt soluble aqueous solution is colorless
Sodium salt soluble
Barium hydroxide BaOH soluble white solid
Barium sulfate BaSO4 is insoluble in water, acid white solid
p>Barium carbonate BaCO3 Insoluble in water white solid
Calcium hydroxide CaOH Slightly soluble white solid
Calcium sulfate CaSO4 Slightly soluble white solid
Carbonic acid Calcium CaCO3 insoluble in water white solid
Magnesium hydroxide Mg(OH)2 insoluble in water white solid
Magnesium sulfate MgSO4 soluble white solid
Magnesium carbonate CaCO3 Slightly soluble white solid
Aluminum hydroxide Al(OH)3 Insoluble in water white solid
Aluminum sulfate Al2(SO4)3 soluble white solid
Hydroxide Manganese Mn (OH) 2 Insoluble in water white solid
Manganese carbonate MnCO3 Insoluble in water white solid
Zinc hydroxide Zn (OH) 2 Insoluble in water white solid
Zinc carbonate ZnCO3 is insoluble in water, white solid
Iron hydroxide Fe(OH)2 is insoluble in water, white solid
Fe(OH)3 is insoluble in water, reddish brown solid
Iron carbonate FeCO3 is insoluble in water-white solid
Copper hydroxide Cu(OH)2 is insoluble in water-blue solid
Copper carbonate CuCO3 is insoluble in water-white solid
Silver chloride AgCl Insoluble in water white solid
Silver sulfate Ag2SO4 Slightly soluble white solid
Silver carbonate Ag2CO3 Insoluble in water white solid
Nitrate solution
Hydrochloride solution (except silver chloride)
Ferrous iron salt solution is generally green
Ferric iron salt solution It is usually yellow
Copper salt solution is usually blue-green
This is what I found for you online, I hope you can use it.
Naming positive ion elements
How to classify acids, bases and salts
It’s very simple. A compound in which all the cations generated during ionization are hydrogen ions (H) is called an acid. . Simply put, acids are compounds containing hydrogen radicals. Like HCl, H2SO4, HNO3, etc., acids have five general properties: 1 reacts with indicators, 2 reacts with active metals for displacement, 3 reacts with alkaline oxides, 4 reacts with certain salts, and 5 reacts with bases for neutralization. .
Alkali is the general name for compounds containing hydroxyl groups, such as Ca (OH) 2, NaOH, KOH, etc. Alkali have four general properties: 1. Alkaline solutions can interact with acid-base indicators Reaction, 2. Alkali can react with acid to generate salt and water, 3. Alkaline solution can react with non-metal oxides to generate salt and water, 4. Alkaline solution can react with salt to generate new base and new salt.
Salt, of course, is not the one you eat (- -|||). It is a compound composed of metal ions (or ammonium ions NH4) and acid ions, that is, a combination of metal elements and acid ions, like NaCl , Na2CO3, KCl, etc.
I played so hard, LZ wants to give me extra points~~ How to classify acids, bases and salts
Acid
According to the acid radical, it can be divided into (1 ) Oxygen-containing acids (HNO3.H2SO4, etc.) (2) Anaerobic acids (HCL.HI, etc.)
Can be divided according to the number of ionized H (1) Monobasic acids (HCL.HI, etc.) (2 ) Dibasic acid (H2SO4.H2CO3, etc.) (3) Polybasic acid (H3P04, etc.)
According to strength (1) Strong acid (HCL.H2SO4, etc.) (2) Weak acid (H2CO3, etc.)
Base
According to the strength (1) Strong base (NAOH, KOH, etc.) (2) Weak base (FE (OH) 3, etc.)
According to the ionized Number of OH-(1) Monobasic bases (NAOH.KOH, etc.) (2) Dibasic bases (Ba(OH)2.Ca(OH)2, etc.) (3) Polybasic bases (Fe(OH)3, etc.)
Salt
(1) Normal salt (Na2CO3.Na2SO4, etc.) (2) Acid salt (NaHC03.NaHSO4, etc.) (3) Basic salt (Cu2(OH)2CO3, etc.
I hope it will be adopted. Thank you for your help. What are the classifications of acids, alkalis and salts in chemistry?
There are two ways to classify acids: 1. According to the presence or absence of oxygen elements, they are divided into anaerobic acids and acid-containing acids. Oxyacids Anaerobic acids: do not contain oxygen elements, and are named "hydrogen acids", for example, HCl hydrochloric acid, oxyacids: oxygen-containing elements, except hydrogen and oxygen when naming, use the name of the third element is "a certain acid" Example: H 2 SO 4 - sulfuric acid. The number of hydrogen ions produced when an acid molecule is ionized: Monobasic acid: one acid molecule ionizes to produce one H, for example HCl, HNO 3 Dibasic acid: one acid molecule Two H atoms are ionized, such as H 2 SO 4 and H 2 CO 3. Tribasic acid: One acid molecule ionizes to produce three H atoms, such as H 3 PO 4. There are many types of salts: 1. Oxygen-containing acid salts refer to salts containing The salt corresponding to the oxyacid, such as Na2SO4 corresponding to H2SO4, and Na3PO4. The anoxic acid salt refers to the salt corresponding to the oxyacid, such as Na2S corresponding to H2S. 2. Normal salt: The acid and alkali are completely neutralized. Product. For example: NaCL Acid salt: a salt containing hydrogen ions in the cation. For example: NAHSO4 Basic salt: a salt containing hydroxide ions in the anion. For example: Cu2(OH)2CO3 Double salt: composed of two or two kinds. Isomorphic compounds composed of the above simple salts are called double salts. Double salts are also called heavy salts.
Complex salts contain some ions of similar size and suitable for the same crystal lattice, such as alum (potassium aluminum sulfate) KAl (SO4)2·12H2O. Mixed salt: refers to a metal ion that can be divided into soluble bases (all strong except TiOH). Alkali), and insoluble bases (both weak bases), but there are also new theories that propose that the protons accepted in the reaction are alkalis that help empty the digestive tract--not only whether it is Mg(OH)2, Because MgSO4 is Epsom salt, it is hydrolyzed~ It is used as an alkali for making soap------NaOH. It is used as an alkali for washing mirror frames or glass-----It is not clear, but strong alkali must react with SiO2 for agricultural use. It is used as an alkali for chemical fertilizers or medical purposes - ammonia monohydrate (NH3.H2O weak base); as an alkali for building materials - a salt composed of Ca(OH)2 slaked lime and various acid ions. Such as calcium nitrate chloride Ca(NO3)Cl Classification of acid and alkali salts (the more complete the better)
Name Molecular formula Solubility state
Nitric acid HNO3 solution
Hydrochloric acid HCl solution
Sulfuric acid H2SO4 solution (high concentration, similar to oil)
Carbonic acid H2CO3 solution, easily volatile
Ammonia NH3·H2O Solution state, easily volatile
Ammonia salt soluble
Potassium salt aqueous solution colorless
Sodium salt soluble
Barium hydroxide BaOH soluble White solid
Barium sulfate BaSO4 Insoluble in water, acid white solid
Barium carbonate BaCO3 Insoluble in water white solid
Calcium hydroxide CaOH Slightly soluble white solid
Calcium sulfate CaSO4 slightly soluble white solid
Calcium carbonate CaCO3 insoluble in water white solid
Magnesium hydroxide Mg(OH)2 insoluble in water white solid
p>
Magnesium sulfate MgSO4 soluble white solid
Magnesium carbonate CaCO3 slightly soluble white solid
Aluminum hydroxide Al (OH) 3 insoluble in water white solid
Aluminum sulfate Al2 (SO4) 3 soluble white solid
Manganese hydroxide Mn (OH) 2 insoluble in water white solid
Manganese carbonate MnCO3 insoluble in water white solid
Zinc hydroxide Zn(OH)2 is insoluble in water, white solid
Zinc carbonate ZnCO3 is insoluble in water, white solid
Iron hydroxide Fe(OH)2 is insoluble in water White solid
Fe(OH)3 Insoluble in water reddish brown solid
Iron carbonate FeCO3 Insoluble in water white solid
Copper hydroxide Cu(OH)2 Insoluble in water blue solid
Copper carbonate CuCO3 Insoluble in water white solid
Silver chloride AgCl Insoluble in water white solid
Silver sulfate Ag2SO4 Slightly soluble white Solid
Silver carbonate Ag2CO3 insoluble in water white solid
Nitrate soluble
Hydrochloride soluble (except silver chloride)
The divalent iron salt solution is usually green
The ferric iron salt solution is usually yellow
The copper salt solution is usually blue-green. What are the tips for learning acid and alkali salts
Pay attention to the reaction conditions and product types of each type of reaction
(1) Metallic acid -------- Salt hydrogen gas (displacement reaction)
Hydrogen Pre-metallic acid is hydrochloric acid or dilute sulfuric acid.
(2) Metal element salt (solution) ------- Another metal another salt
The metal element is the pre-metal in the salt (potassium, calcium, sodium Except), the salt must be soluble in water.
(3) Basic oxide acid --- salt water
Acid is soluble in water
(4) Acidic oxide alkali - ------- Salt water
Alkali are soluble in water (not metathesis reaction)
(5) Acids and bases----- Salt water
At least one of the acid and the alkali is soluble in water
(6) Acid salt----another acid and another salt
The salt in junior middle school is insoluble. It is a carbonate, acid-soluble, and generates gas
The reactants are all soluble in water, and the salt formed is a precipitate
(7) Alkali salt-------- Another alkali and another salt
The reactants must be soluble. The ammonium salt will generate gas, but the ammonium salt will precipitate
(8) Salt---- - Two new salts
The reactants must be soluble, and the products are precipitated. What is the difference between an acid-base salt solution and an acid-base salt aqueous solution?
The acid mentioned in high school and junior high school Alkali salt solutions are generally aqueous solutions
There are less cases where they are not aqueous solutions. They are mainly non-polar molecules, such as chlorine gas dissolved in organic solvents, and the mutual solubility of organic substances.
Acid solutions, salt solutions, alkaline solutions, etc. that appear when solving problems in middle school are generally their aqueous solutions acid-base salt classification table
Explanation of the properties of acids, bases, and salts
Acid-base salts One chapter can be said to be the application and synthesis of the entire junior high school chemistry knowledge. On the basis of the basic concepts and theories of chemistry, it summarizes the rules for learning inorganic chemistry by explaining the basic properties of acids, bases, and salts, that is, by studying a specific thing, mastering the rules, and then drawing a class The nature of things has a very enlightening effect on our learning of knowledge, especially the course of chemistry. Below we will explain acid-base salts from several aspects.
1. Accurately grasp the concepts of acid, alkali and salt, and clarify their essential differences
The chapter on acids, bases and salts has many concepts. Whether you can correctly understand the concepts is the key to learning acidity well. , alkali and salt prerequisites.
1. Acids and acid properties
As for the definition of acid, we say that all cations generated during ionization are H. What we need to pay special attention to here are the keywords "cation", "all" and "H". Below we take common sulfuric acid and hydrochloric acid as examples to illustrate the properties of acids.
Properties of acids: hydrochloric acid sulfuric acid
Acid makes purple litmus test solution turn red, but colorless phenolphthalein test solution does not change color. Hydrochloric acid turns purple litmus test solution red, but colorless phenolphthalein test solution does not change color. Sulfuric acid makes purple litmus test solution turn red, but colorless phenolphthalein test solution does not change color.
Metallic acid → salt hydrogen Zn 2HCl=ZnCl2 H2↑ Zn H2SO4 =ZnSO4 H2↑
Alkaline oxide acid → salt water Fe2O3 6HCl=2FeCl3 3H2O Fe2O3 3H2SO4=Fe2(SO4) 3 3H2O
Alkaline acid → salt water NaOH HCl=NaCl H2O Cu(OH)2 H2SO4= CuSO4 2H2O
Hydrochloric acid → another salt another acid AgNO3 HCl=AgCl↓ HNO3 BaCl2 H2SO4=BaSO4↓ 2HCl
Note:
(1) In 'metal acid → salt hydrogen', the acid usually refers to dilute sulfuric acid and dilute hydrochloric acid, not concentrated sulfuric acid or nitric acid.
Because concentrated sulfuric acid or nitric acid has strong oxidizing properties, it cannot generate hydrogen gas when reacting with metals but generates water; metals refer to active metals that are ranked before 'hydrogen' in the metal activity sequence, and metals that are ranked after 'hydrogen' It cannot replace the hydrogen in the acid.
(2) Export the metal activity sequence table through the reaction between metal and acid:
K Ca Na Mg Al Zn Fe Sn Pb (H) Cu Hg Ag Pt Au
p>
The activity of metal gradually weakens from strong to strong
In the order of metal activity, the higher the position of the metal, the stronger the activity, the more violent the reaction, and the shorter the time required.
(3) Concentrated sulfuric acid is water absorbent and is usually used as a desiccant. Sulfuric acid is also dehydrating and can be very corrosive to panels or clothing. When diluting concentrated sulfuric acid, be sure to slowly inject the concentrated sulfuric acid into the water along the wall of the container and stir continuously. Never pour water into the concentrated sulfuric acid. If water is injected into the concentrated sulfuric acid, the density of the water will be small and it will float. On top of sulfuric acid, the heat released during dissolution will cause the water to boil immediately, causing the sulfuric acid liquid to splash around, which is prone to accidents.
2. Bases and properties of bases
Similar to acids, we can define bases as: the anions generated during ionization are all OH- ions. Here we also need to pay special attention to the keywords "anion", "all", and "OH-". Below we take the common sodium hydroxide and calcium hydroxide as examples to illustrate the properties of alkali.
Common alkalis and their properties
Alkali properties: sodium hydroxide and calcium hydroxide
Alkali turns purple litmus solution blue, making Colorless phenolphthalein test solution turns red. Sodium hydroxide turns purple litmus test solution blue and colorless phenolphthalein test solution turns red. Calcium hydroxide turns purple litmus test solution blue and colorless phenolphthalein test solution red.
Acidic oxide alkali → brine 2NaOH CO2=Na2CO3 H2O Ca(OH)2 CO2=CaCO3↓ H2O
Acid-base → brine NaOH HCl=NaCl H2O Ca(OH)2 H2SO4 = CaSO4 2H2O
Salt-alkali→another salt another alkali 2NaOH CuSO4=Na2SO4 Cu(OH)2↓ Ca(OH)2 Na2CO3=CaCO3↓ 2NaOH
Note:
(1) Only soluble bases can react with some non-metal oxides, which are acidic oxides. Most acidic oxides are soluble in water and combine with water to form acids.
(2) When salt and alkali react, both must be soluble and one of the products is precipitated for the reaction to proceed.
(3) Writing chemical equations for the reaction of bases with certain metal oxides
Some people find it difficult to write chemical equations for this type of reaction. For this reason, you can first write a very The chemical equation of a metal oxide reacting with water to form an oxygen-containing acid, and then writing the product by exchanging components between the oxygen-containing acid and the base. The two equations are combined into one chemical equation. For example, the reaction between sulfur trioxide and sodium hydroxide:
3. Salt and the properties of salt
Regarding the concept of salt, we can think of it this way: after acid and alkali ionization, ion exchange generates salt and water. For example, we think of NaCl as the product of the ionization of HCl and NaOH.
Common salts and chemical properties of salts
Examples of salt properties
Salt solution metal → salt ˊ metal ˊ CuSO4 Zn= ZnSO4 Cu
Hydrochloric acid→saltˊ acidˊ BaCl2 H2SO4=BaSO4↓ 2HCl
Salt solution Alkaline solution→saltˊ alkaliˊ 3NaOH FeCl3=3NaCl Fe(OH)3 ↓
Salt solution Salt solution → saltˊ saltˊ AgNO3 NaCl=AgCl↓ NaNO3
Note:
In the metal activity sequence table, only the metal ranked first can remove the metal ranked later from the metal activity sequence table. displaced from their salt solution. However, the reactions between K, Ca, and Na metals and salt solutions are special and are not required here.
2. Clarify the nature of the metathesis reaction and master the rules of acid-base and salt reactions
1. Metathesis reaction and the conditions for its occurrence
The definition of metathesis reaction is: a reaction in which two compounds exchange components with each other to generate two other compounds.
General formula: AB CD=AD CB
Conditions for occurrence: two substances exchange ions with each other in the solution. If there is precipitation, gas release or water generation in the product , metathesis reactions can occur.
2. Use the conditions for the metathesis reaction to correctly write the chemical equations involved in this chapter
Many students have memorized the properties of acids, bases and salts, but when exposed to specific reactions that occur with specific substances, use chemical equations It's difficult to express. There are two ways to solve this difficulty: first, when learning the properties of acids and bases, practice writing the relevant chemical equations repeatedly. Once these two parts are mastered, learning the properties of salt will be easy; the second is to learn by yourself. Appendix III at the back of the book is "Solubility Table of Some Acids, Alkalis and Salts", from which you can find out the rules of solubility and insolubility, practice writing chemical equations related to reactions, and consolidate the metathesis reaction conditions while writing. After practicing this many times, you will feel that writing the chemical equation of the metathesis reaction is regular and not difficult.
3. The reaction between alkali and acidic oxides is not a metathesis reaction
3. Memorize the solubility of acids, alkali and salts
The solubility of acids, alkali and salts is a key factor to determine whether the metathesis reaction is possible. An important basis for the occurrence, here we provide you with a memory tip:
Potassium, sodium, ammonium and nitrates are all soluble salts.
Sulfate is insoluble in barium and lead; acid is soluble and alkali is insoluble.
Chloride is insoluble, silver, mercury, and carbonate are mostly insoluble.
4. Testing of several common ions
Testing of Cl-, ,
Experimental operation Experimental phenomenon Experimental conclusion Chemical equation
Cl- Take a small amount of sample in a test tube, add AgNO3 solution and dilute HNO3 dropwise, and a white precipitate insoluble in dilute nitric acid will form. The sample contains Cl-
AgNO3 KCl=AgCl↓ KNO3
Take Put a small amount of sample into a test tube, add Ba(NO3)2 solution and dilute HNO3 dropwise, and a white precipitate insoluble in dilute nitric acid will form. The sample contains Ba(NO3)2 H2SO4=BaSO4↓ 2HNO3
Take a small amount of sample in a test tube, add dilute HCl dropwise, pass the generated gas into the clear lime water, a colorless gas will be generated, and the gas will turn the clear lime water turbid. The sample contains
K2CO3 2HCl=2KCl CO2↑ H2O
CO2 Ca(OH)2= CaCO3↓ H2O
Oops, it doesn’t know the table. Use the one below. There is no table.
Acid-base Summary of salt knowledge
1. Concept:
1. The composition of acids - hydrogen ions + acid ions
2. The composition of bases - metal ions + Hydroxide ion
3. The composition of salt - metal ion + acid ion
4. Metathesis reaction - two compounds exchange components with each other to generate two other compounds. The reaction is called metathesis reaction. AB CD=AD CB
5. The method of diluting concentrated sulfuric acid - be sure to slowly inject concentrated sulfuric acid into the water along the wall of the container, and stir continuously to allow the heat generated to diffuse quickly, cutting Do not pour water into concentrated sulfuric acid.
6. Neutralization reaction - The reaction in which acid and alkali react to form salt and water is called neutralization reaction.
2. Memorize the valence formula of common elements and atomic groups:
(positive price) Potassium monohydrogen sodium silver, dicalcium magnesium barium zinc, trialuminum, tetrasilicon, pentanitrogen phosphorus.
(Negative valence) Negative one valence: fluorine, chlorine, bromine, iodine;
Negative two valence: oxygen and sulfur.
(variable positive price): one and two copper mercury, two and three iron, two and four carbon, four and six sulfur.
(Valency of atomic groups
Negative valence: hydroxide (OH), nitrate (NO3), chlorate (ClO3), permanganate (MnO4);
p>
Negative divalent: sulfate (SO4), carbonate (CO3), sulfite (SO3), manganate (MnO4);
Negative trivalent: phosphate (PO4) ;
Positive monovalent: ammonium radical (NH4).
3. Memorize the following reaction equation:
(1) Properties of acid (1) and The purple litmus test solution turns red when the indicator reacts, and the colorless phenolphthalein test solution does not change color.
(2) Acid + alkali = salt + water
(3) Acid + certain. Some metal oxides = salt + water.
(4) Acid + active metal = salt + hydrogen gas.
(5) Acid + salt = new salt + new acid. p>
1. Reaction of zinc with dilute hydrochloric acid: Zn 2HCl = ZnCl2 H2 ↑ Bubbles are generated, and the zinc particles gradually decrease.
2. Reaction of zinc with dilute sulfuric acid: Zn H2SO4 = ZnSO4 H2 ↑
3. Reaction of iron with dilute hydrochloric acid: Fe 2HCl = FeCl2 H2 ↑ Bubbles are generated, and the iron gradually decreases.
4. Reaction of iron with dilute sulfuric acid: Fe H2SO4 =FeSO4 H2 ↑ Solution Turns into light green.
5. The reaction between rust and dilute hydrochloric acid: Fe2O3 6HCl = 2FeCl3 3H2O. The red rust gradually disappears.
6. The reaction between rust and dilute sulfuric acid: Fe2O3 3H2SO4 = Fe2(SO4)3 3H2O solution Turns yellow
7. Reaction of copper oxide with dilute hydrochloric acid: CuO 2HCl =CuCl2 H2O Black copper oxide gradually disappears,
8. Reaction of copper oxide with dilute sulfuric acid: CuO H2SO4 = CuSO4 The H2O solution turns blue.
(2) Properties of alkali: (1) Alkaline solution can turn purple litmus test solution blue and colorless phenolphthalein test solution red.
(2) Alkali + most non-metal oxides = salt + water
(3) Alkali + acid = salt + water
(4) Alkali + Certain salts = another salt + another alkali
1. The reaction of sodium hydroxide and carbon dioxide: 2NaOH CO2 = Na2CO3 H2O
2. The reaction of sodium hydroxide and sulfur dioxide: 2NaOH SO2 = Na2SO3 H2O
3. Reaction of sodium hydroxide and sulfur trioxide: 2NaOH SO3 = Na2SO4 H2O
4. Reaction of calcium hydroxide and carbon dioxide: Ca(OH)2 CO2 = CaCO3↓ H2O makes clear lime water turbid
5. Reaction of sodium hydroxide and dilute sulfuric acid: 2NaOH H2SO4 = Na2SO4 2H2O
6. Reaction of sodium hydroxide and dilute hydrochloric acid: NaOH HCl = NaCl H2O
7. Reaction of quicklime with water: CaO H2O =Ca(OH)2
(3) Properties of salt: (1) Salt + certain metals = another One salt + another metal.
(2) Salt + certain acid = another salt + another acid.
(3) Salt + certain alkali = another salt + another alkali
(4) Salt + certain salt = another salt + another salt
1. Reaction of copper sulfate solution with iron: CuSO4 Fe = ZnSO4 Fe. The iron surface is covered with red substance, and the solution changes from blue to light green
2. Reaction of sodium carbonate with hydrochloric acid: Na2CO3 2HCl = 2NaCl H2O CO2↑There are bubbles and the solid gradually decreases
3. Reaction of sodium bicarbonate and hydrochloric acid: NaHCO3 HCl = NaCl H2O CO2↑There are bubbles and the solid gradually decreases
4. Limestone reacts with dilute hydrochloric acid: CaCO3 2HCl = CaCl2 H2O CO2↑ bubbles are produced and the solid gradually decreases
5. Silver nitrate reacts with dilute hydrochloric acid: AgNO3 HCl = AgCl↓ HNO3 white precipitate is produced
6. Reaction of barium chloride and dilute sulfuric acid: BaCl2 H2SO4 = BaSO4↓ 2HCl produces white precipitate
7. Reaction of calcium hydroxide and sodium carbonate solution: Ca(OH)2 Na2CO3 = 2NaOH CaCO3↓ A white precipitate is produced
8. The reaction between silver nitrate solution and sodium hydroxide solution: AgNO3 NaCl = AgCl↓ NaNO3 is produced. A white precipitate is produced
9. Barium chloride solution and sodium sulfate solution Reaction: BaCl2 Na2SO4 = 2NaCl BaSO4↓A white precipitate is produced
4. Metal activity sequence:
K Ca Na Mg Al Zn Fe Sn Pb (H) Cu Hg Ag Pt Au
5. Solubility table:
(1) Most acids are soluble (HCl, HNO3, and H2CO3 are volatile, and concentrated H2SO4 is water-absorbent.)
(2) Solubility of alkali: Potassium, sodium, barium, ammonium are soluble, calcium is slightly soluble, and other alkali are completely insoluble.
(3) Solubility of salt:
Potassium, sodium, ammonium and nitrate are soluble in tetra salts.
Except for AgCl, which is insoluble, all chlorides are completely soluble.
Except for BaSO4 which is insoluble and Ag2SO4 and CaSO4 which are slightly soluble, sulfates are completely soluble.
Except for potassium, sodium, and ammonium salts, which are completely soluble and MgCO3 is slightly soluble, the carbonates are completely insoluble.
6. Reaction conditions:
1. Conditions for metathesis reaction - there is precipitation in the product, or gas is released, or water is generated
2. Conditions for the reaction of metals with acids -
(1) In the order of metal activity, metals should be ranked before hydrogen.
(2) Concentrated sulfuric acid and nitric acid cannot generate hydrogen gas when reacting with metals.
(3) When iron undergoes a substitution reaction, a +2-valent iron compound is produced.
3. Conditions for the reaction of metals with salts -
(1) In the metal activity sequence table, elemental metals are more active than metals in salts.
(2) The salt in the reactants must be soluble.
(3) Metals such as K, Ca, Na, and Ba cannot react with salts to form another salt or another metal.
4. The conditions for the reaction of salt and salt - the reactants must be soluble and the products must be precipitated.
5. Conditions for the reaction of salt and alkali - the reactants must be soluble, and the products must have precipitation or gas.
7. Memorize the common names and chemical formulas of common substances:
Quick lime - CaO Hydrated lime - Ca(OH)2 Limestone, marble - CaCO3
Table salt - NaCl Fire soda, caustic soda, caustic soda - NaOH Soda ash, soda - Na2CO3
Baking soda - NaHCO3 Rust, hematite - Fe2O3 Hematite - Fe3O4
Diamond, graphite - C Dry ice - CO2 ice - H2O
Natural gas (methane) - CH4 Alcohol (ethanol) - C2H5OH Acetic acid (acetic acid) - CH3COOH
8. Memorize the colors of common substances:
Red solids - Cu, Fe2O3, P (red phosphorus)
Black solids - C, CuO, Fe3O4, FeO, MnO2
White solid - KClO3, P2O5, P (white phosphorus), CuSO4 (anhydrous copper sulfate), KCl, NaCl, etc.
Dark purple solid - KMnO4 yellow Solid - S
Blue solid - CuSO4?5H2O Blue flocculent precipitate - Cu (OH) 2
Reddish brown flocculent precipitate - Fe (OH ) 3 Common white precipitates that are insoluble in acid - BaSO4, AgCl
White precipitates that are soluble in acid and release gases that turn clear lime water turbid - precipitates of insoluble carbonates such as BaCO3 and CaCO3
White precipitate that is soluble in acid but does not produce gas - precipitation of insoluble bases such as Mg(OH)2, Al(OH)3 etc.
Blue solution - CuSO4, CuCl2 , Cu(NO3)2 and other Cu2+-containing solutions
Light green solutions - FeSO4, FeCl2 and other Fe2+-containing solutions
Yellow solutions - FeCl3, Fe2(SO4)3, Fe (NO3) 3 and other solutions containing Fe3+
9. Inspection and identification of substances:
1. Test dilute hydrochloric acid (or Cl-) - take a small amount of the liquid to be tested in a clean In the test tube, drop a few drops of AgNO3 solution and dilute HNO3, and a white precipitate will appear.
2. Test dilute sulfuric acid (or SO42-) - Take a small amount of the liquid to be tested in a clean test tube, add a few drops of BaCl2 solution and dilute HNO3, and a white precipitate will appear.
3. Testing CO32--Put a small amount of the liquid to be tested into a clean test tube, and add a few drops of dilute HCl to produce gas that will turn the clear lime water into turbid.
4. Test NH4+ - Put a small amount of the substance to be tested into a clean test tube, drop in an appropriate amount of NaOH solution and heat it, which will turn the wet red litmus paper into blue gas.
5. Identify dilute hydrochloric acid and dilute sulfuric acid - Take a small amount of the liquid to be tested in two clean test tubes, and drop a few drops of BaCl2 solution into each. The original solution with white precipitate is dilute sulfuric acid. The original solution that produces no phenomenon is dilute hydrochloric acid.
6. Identify Ca(OH)2 and NaOH solutions—Put a small amount of the liquid to be tested into two clean test tubes, and pass in CO2 gas (or add a few drops of Na2CO3 solution each). The original solution with white precipitate is Ca(OH)2, and the original solution with no phenomenon is NaOH.
◎Supplement the following reaction equation:
1. Reaction of copper hydroxide with dilute hydrochloric acid: Cu(OH)2 2HCl = CuCl2 2H2O The blue precipitate disappears
2. Reaction of copper hydroxide with dilute sulfuric acid: Cu(OH)2 H2SO4 = CuSO4 2H2O turns into blue solution
3. Reaction of sodium hydroxide with copper sulfate solution: 2NaOH CuSO4 = Na2SO4 Cu(OH) 2 ↓ A blue precipitate is produced
4. The reaction between sodium hydroxide and ferric chloride solution: 3NaOH FeCl3 = Fe(OH)3↓ 3NaCl produces a reddish-brown precipitate
◎Judgment The acidity and alkalinity of a solution is expressed by an indicator, and the acidity and alkalinity of a solution is expressed by pH.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Neutral
← Acidic enhancement Alkaline enhancement→
Purple litmus is colorless phenolphthalein
pHlt; 7 is acidic and appears red and colorless
pH=7 is neutral and appears purple and red
pHgt ; 7 means alkaline, blue and red.
◎Selection of desiccant:
1. Concentrated sulfuric acid can dry: acidic gases (such as: CO2, SO2, SO3, NO2, HCl,)
Neutral gases (such as: H2, O2, N2, CO)
※Alkaline gases (such as: NH3) cannot be dried
2 , sodium hydroxide solid, quicklime, soda lime can be dried: alkaline gas (such as: NH3)
Neutral gas (such as: H2, O2, N2, CO)
※ Cannot dry acidic gases (such as: CO2, SO2, SO3, NO2, HCl,)
3. Anhydrous copper sulfate solid turns from white to blue when exposed to water, which can detect the presence of water and absorb water vapor. .