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The chemistry equation for the second year of high school is as follows:
1. Aluminum and hydrochloric acid: 2Al+6HCl=2AlCl3+3H2 gas.
2. Aluminum and sulfuric acid: 2Al+3H2SO4=Al2(SO4)3+3H2 gas.
3. Aluminum and sodium hydroxide: 2Al+2NaOH+H2O=2Naalo2+3H2 gas.
4. Aluminum hydroxide heating is divided into 2AL (OH) 3 = (heating) AL2O3 + H2O.
5. Aluminum sulfate and ammonia: Al2(SO4)3 6NH3, H2O 2AL(OH)3 precipitation 3(NH4)2SO4.
6. Alumina and hydrochloric acid: Al2O3 6HCl=2ALCL3+3H2O.
7. Alumina and sodium hydroxide: Al2O3+2NaOH=2Naalo2+H2O.
8. Aluminum chloride and sodium hydroxide: AlCl3 + 3NaOH = Al(OH)3 precipitation + 3NaCl.
9. Aluminum hydroxide and sodium hydroxide: Al(OH)3 NaOH=Naalo2+2H2O.
10. Aluminum chloride and sodium hydroxide: AlCl3+4NaOH=Naalo2+2H2O.
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Electrolysis = 2NaOH + H2 + Cl2
cl2+cu=cucl2;3Cl2+2Fe=2FeCl3 (These 3 are more classic, and the whole writing is incomplete.) )
11.Tested with agno3, if there is cl-, there is a white precipitate. If there is br-, it has a light yellow color. If there is cl-, there is a yellow precipitate.
The ionic equations are: ag+
Cl-AGCL (white precipitate);
ag+br-
AGBR (light yellow precipitate); ag+
i-AGI (yellow precipitate).
12.Total equation: Zn+H2SO4=ZnSO4+H2 The electrons flow from the negative electrode to the positive electrode, then the current flows from the positive electrode to the negative electrode.
Negative electrode: Zn as negative electrode, Zn2E-
Zn2+ cathode: Cu is the cathode, 2H+2E-
Ignition = SO2, SO2 + H2O = H2SO3, 2H2SO3 + O2 = 2H2SO4
Concentrate) + 2NaCl = Heating = Na2SO4 + 2HCl
Concentrate) = Heating = CuSO4 + 2H2O + SO2
2H2SO4 (concentrated) + C = CO2 +2SO2 +2H2O
16.The chemical equation is: Na2SO4 + BACL2 = NaCl2 + BaSO4
Ion equation: SO42-
ba2+baso4↓
High temperature and high pressure catalyst = 2NH3; N2 + O2 = Discharge = 2NO
High temperature and high pressure catalyst = 2NH3;
Reversible symbol) NH4+H2O
H+ Since ammonium ions are hydrolyzed, the concentration of ammonium ions is less than that of chloride ions.
Electrolysis = Cu + Cl2
High temperature = F3O4 + 4H2
High temperature = 2Fe + Al2O3
Heating = 2al(OH)3+3h2
h+alo2-
Heating = Fe3O4 + 4H2
High temperature = 2Fe + Al2O3
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Upstairs, it's thin, not thick.
Fe3O4 + 10Hno3 concentrate = 3Fe (No3) 3 + No2 (arrow) + 5H2O
3Fe3O4+28Hno3 (dilute) = 9Fe(NO3)3+NO+14H20
Fe3O4+8Hi==3FE2+4H2O+I2 (Fe3O4 can be regarded as Fe2O3·FEO, Fe3+ oxidizable I- is I2), condition: no special conditions (can be regarded as no condition).
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Upstairs trim error!
3Fe3O4+28Hno3 (concentrated) = 9Fe(NO3)3+NO+14H20
fe3o4+8hi==3fei2+4h2o+i2
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Bringing it to the exam room? You're cheating! It's better not to do that!
It's easy to spot! Finding out is 0 points... It's the final exam, and you don't want your family to scold you, if you are discovered, you can't get by!
You should take the test honestly, even if you fail the test, it is better than cheating on the exam and being discovered!
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The high one is mainly a redox problem, and it is necessary to clarify the elemental valency of reactants and the resulting species, and the same is true for the ion equation.
High oxygen loss and low also.
The valency becomes higher and loses electrons, is oxidized, and the reducing agent undergoes an oxidation reaction to produce oxidation products.
The valency becomes lower to obtain electrons, which are reduced, and the oxidant undergoes a reduction reaction to produce a reduction product.
The oxidation of oxidation products is weak by oxidants, and the reducing properties of reducing products are weak by reducing agents.
The representation can be expressed by a two-wire bridge and a single-line bridge, the two-wire bridge is easy to express and is better used in reactions with many valence changes, and the single-wire bridge is faster in the redox simpler reaction formula.
The total reaction equation redox gains and losses should be balanced, so the relative numbers in the reactants and products can be derived from this.
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I don't think I need to answer this question professionally, because it would be very difficult to get started. First, the number of each element in the equation should be conserved; Secondly, the transfer of electrons should be conserved (this is very important in the second and third years of high school, and it is basically used). In the first year of high school, it is necessary to follow the current order, but in the second or third year of high school, it should be used upside down, that is, first transfer the conservation of electricity and then the conservation of numbers.
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Redox trimming.
Three steps: 1. Conservation of electrons.
2. Conservation of electric charge.
3. Conservation of atoms.
Chemical equation.
It is a formula in which the equation is equal to the left (or arrow) of each reactant and the right is the chemical formula of each product. For example, hydrogen and oxygen react to produce water >>>More
Hey, I don't even want to write about it, didn't you learn all this in the academy?
1. Zinc and dilute sulfuric acid: Zn + H2SO4 = ZnSO4 + H2 2, iron and dilute sulfuric acid: Fe + H2SO4 = FeSO4 + H2 3, magnesium and dilute sulfuric acid: >>>More
agno3+nacl=agcl()+nano3 ag+ +cl+=agcl
bacl2+na2so4=baso4+2naclcuso4+na2s=cus+naso4 >>>More
Conservation of electric charge. Manganese changes from 7-valent to 2-valent, giving five electrons. The oxygen in hydrogen peroxide changes from negative 1 valence to 0 valence oxygen, losing two electrons. >>>More