-
Analysis: Breaking point: A reacts with A to obtain two substances, B and C
B reacts with B to give two substances, A and D
It is known that we are both metals, and if they react with metals to obtain two products, then A and B should be acids or salts.
He also tells us that "the process of reacting B and B to obtain A is one of the methods of smelting A in ancient times", which reminds us of this reaction in middle school chemistry: Fe + CuSO4 = Cu + FeSO4, and there is a classical Chinese material "Zeng Qing has turned iron into copper". This is the breakthrough.
Then: B: Fe B: CuSO4 A: Cu D: FeSO4
A: concentrated sulfuric acid C: SO2 C: O2 G: SO3 E: Fe(OH)2 F: Fe(OH)3
1) The chemical formula of A is: Cu The chemical formula of C is: O2
2) The chemical program of the reaction between A and A: Cu + 2H2SO4 (concentrated) = Heating = CuSO4 + SO2 + H2O
3) D reacts with NaOH to produce E: Fe2+ +2Oh- = Fe(OH)2
-
Summary. d is elemental, and the content in the earth's crust ranks fourth. Depending on the abundance of elements in the earth's crust, d is likely to be aluminium (Al), the chemical formula and c are oxides, and b c indicates a transformation relationship.
Now we know that d is aluminium (al), so b may be alumina al2o3 and c may be al(oh)3. Then the conversion of B to C can be expressed as: Al2O3 + 3H2O 2Al(OH) is used to modify acidic soil, most likely limestone or quicklime.
The main component of limestone is calcium carbonate (CaCO3), and quicklime is calcium oxide (CaO). The reaction equation of f and h can be expressed as: cao + h2so4 caso4 + chemical equation of reaction with i:
The equation for the reaction of calcium oxide (CaO) with hydrochloric acid (HCl) can be expressed as: CA + 2HCl CaCl2 + H2O In this reaction, calcium oxide reacts with hydrochloric acid to form calcium chloride (CaCl2) and water (H2O). The chemical equation for the reaction of g and h:
If G is sodium hydroxide (NaOH), then the equation for the reaction of G with sulfuric acid (H2SO4) can be expressed as: 2NaOH + H2SO4 Na2SO4 + 2H2O In this reaction, sodium hydroxide reacts with sulfuric acid to form sodium sulfate (Na2SO4) and water (H2O).
d is elemental, and the content in the earth's crust ranks fourth. Depending on the abundance of elements in the earth's crust, d is likely to be aluminium (Al), the chemical formula and c are oxides, and b c indicates a transformation relationship. Now we know that d is aluminium (al), so b may be alumina al2o3 and c may be al(oh)3.
Then the conversion of B to C can be expressed as: Al2O3 + 3H2O 2Al(OH) is used to modify acidic soil, most likely limestone or quicklime. The main component of stone limestone is calcium carbonate (CaCO3), and quicklime is calcium oxide (CaO).
The equation for the reaction of F and H can be expressed as: Cao + H2SO4 CaSO4 + chemical equation for the reaction with I: The equation for the reaction of calcium oxide (CaO) with hydrochloric acid (HCl) can be expressed as:
CA + 2HCl CaCl2 + H2O In this reaction, calcium oxide reacts with hydrochloric acid to form calcium chloride (CaCl2) and water (H2O). Chemical equation for the reaction of G with H: If G is sodium hydroxide (NaOH), then the equation for the reaction of G with sulfuric acid (H2SO4) can be expressed as:
2NaOH + H2SO4 Na2SO4 + 2H2O In this reaction, sodium hydroxide reacts with juvenile sulfuric acid to form sodium sulfate (digging Na2SO4) and water (H2O).
Boss, the chemical formula DFE you wrote?
Ahhhhhhh
-
A, B and C are common substances in junior high school chemistry, and their transformation relationships are as follows:
A = B + C.
B, in turn, can produce C.
1.If A, B, and C all contain three elements, the relative molecular weight of A, B, and C increases, and one of them is widely used in the production of glass, paper, textiles, and detergents. (What substances have these effects?) )
The chemical equation for the conversion of A to B is:
B can also be converted to A, and the chemical equation for the reaction is 2If A, B and C all contain 3 elements, the mass ratio of the two elements is 1:2, in the conditional reaction, one has insoluble matter generation, the other has gas generation, and the third one has insoluble matter and water generation, then the generated gas may be The chemical equation of the reaction from A to C is:
-
a:fe2o3 b:hcl c:fecl3 d:fe(oh)3 e:kcl f: agcl
1) Fe2O3+6HCl===2FeCl3 (2)FeCl3+3KOH===Fe(OH)3 Shen Zedian +3kCl
3) 2Fe(OH)3== Heating ==Fe2O3+3H2O (4) KCl + AGnO3===AGCL sinking and cracking He shed + KNO3
-
A is Cu, B is Cuo, C is Fe, D is FeSo4, and E is H2.
The basic type of reaction is the chemical reaction and the equation is 2Cu + O2 = 2Cuo.
The reaction of E+B is CuO+H2=Cu+H2O.
The reason for the formation of E is that excess dilute sulfuric acid is brought in the previous step, which is replaced with the metal Fe to form H2.
The focus of the whole process is on the color, the metal Cu is red, and Fe2+ (divalent iron ion) is light green.
-
The red metal element of junior high school is only cu (copper).
The first question is: type of reaction:
The process A to B is the reaction of copper and oxygen to produce copper oxide, and the type of reaction should be the chemical reaction second question: Equation : 2Cu + O2 = 2cuo Third question: The chemical formula of c is Fe (iron).
Fourth question: cuo + h2 = cu + h2o (note that there is a small triangle above the equal sign in the middle, which represents heating).
The fifth problem, the cause of the colorless gas E in the transformation: excessive dilute sulfuric acid, which replaces with the added iron to form H2
The reason for judging C as iron is: light green solution D, and only iron sulfide solution learned in junior high school.
-
The basic type of reaction is oxidation reaction.
The equation for its reaction is 2Cu+O2 = (heating) = 2Cuo (red metal elemental is generally Cu).
The chemical formula of C is Fe (because the Fe solution is green) and the chemical equation for the reaction of substances E and B under heating conditions is written H2+CuO=(Heating)=H2O+Cu
The reason for the production of colorless gas E in the conversion is the addition of excess dilute sulfuric acid, so the solute in the X solution has H2SO4 and CuSO4
h2so4+fe=feso4+h2↑
-
The metal Cu is red, while Fe2+ (divalent iron ion) is light green and from this it follows that B is Cuo(2cu+o2=2cuo )
c is cuso4d is feso4 and e is h21Compound 2Cu+O2=2CuO
H2 = Cu + H2O to be heated.
The reason for the formation of E is that excess dilute sulfuric acid is introduced in the process of 2, and the displacement reaction with the metal Fe is formed by H2
-
i contains only one of the so3:
1)o22)b
Analysis: If copper sulfate decomposes to produce only copper oxide and a gas, it can be determined to be SO3 through the conservation of elements
Matches can be rekindled, of course, O2
In that calculation, the reduction of 5 grams in a is the reduction of copper sulfate to copper oxide, which is equivalent to the decomposition reaction of SO3, 5 grams is its mass, and the mass of C remains unchanged, indicating that B has absorbed SO2 SO3, which is equivalent to the 5 grams of SO3 decomposed into a mixture of grams of O2 and grams of SO2 SO3, and we can calculate that the ratio of the amount of CuSO4 to O2 is 4 to 1, which is B.
-
It is impossible to judge without quality changes.
-
I guess how many responses meet this question is not the core question. The key is to train a mind through this question:
1. x + A = B + y
2. x+z=b.
3. Y+Z=A.
Combining reactions two and three can change reaction one to.
x+yz=xz+y
That is, x can replace y. Since there are no other constraints on the question, there are many responses that meet the criteria, which can be divided into four categories:
1. Metal replacement.
2. Metal replaces non-metal.
3. Non-metallic replacement of non-metallic.
4. Non-metallic replacement of metal.
On this basis, you can list no less than 20 possibilities that the teacher said...
Right? Hehe...
-
X is hydrogen, Y is copper, and Z is oxygen.
A is copper oxide and B is water.
As long as certain conditions are met, the two substances A and Y can be used.
A is an oxide that can react with hydrogen, zinc oxide, silica, etc.
y is the corresponding oxide, except for the oxygen element, the remaining element can be composed of element.
3 times. 1'Divide the balls into 4 groups of 3.
2'1 group and 2 groups ratio. If it is not balanced, the irregular balls are in groups 1 or 2. (3 and 4 sets of balls are standard) can choose any group and the 3rd group to compare, (assuming that the lighter group --- 1 group, the same is true for the heavier group). >>>More
It should be put in slowly from top to bottom, because if it is quickly put to the bottom, it will be locally exothermic, difficult to dissipate, and easy to cause.
Carbon dioxide is generated when the candle is burned, and when the candle is just blown out, part of the carbon dioxide is not in a hurry to completely diffuse, and it is covered by the beaker, and the clear lime water on the inner wall of the beaker will become turbid, thus drawing the wrong conclusion). >>>More
Hehe, hello.
I've been in the same situation with mm many times. >>>More