Question 3 High School Chemistry Ask for a master s explanation

C, A: The reason why CO2 does not precipitate is because barium chloride can be generated from barium carbonate through CO2, then another product must be hydrochloric acid, which we all know is impossible, and I think the probability of generating hydrochloric acid and barium sulfite after passing SO2 is not very large.

B: Copper powder is indeed insoluble in dilute sulfuric acid, but after the introduction of nitrate ions, the solution is equivalent to dilute nitric acid, because there are hydrogen ions and nitrate ions, which should be dissolved at this time.

C: Aluminum chloride can not be dissolved in excess of ammonia, because ammonia is a weak alkali, and the sodium bisulfate added can be regarded as a strong acid, and the acid-base neutralization reaction occurs, so the precipitation will disappear.

d: After adding copper sulfate, zinc and copper sulfate undergo a displacement reaction, and a small amount of copper can be generated on the surface of zinc to form a galvanic cell, and the reaction formula will be accelerated, rather than unchanged.

So to sum up: c

Because of the excess carbon dioxide, barium bicarbonate is generated, without precipitation, and after the addition of sulfur dioxide, metathesis reaction occurs to generate barium bisulfite, which is not a precipitation. There are hydrogen ions and nitrate ions in the solution at the same time, which has strong oxidizing properties, and the copper powder will dissolve. d Add copper sulfate solid, dissolve in water and become copper sulfate solution, zinc first reacts with copper ions, and forms countless tiny galvanic cells with the replaced copper, which can accelerate the reaction rate.

Sodium bisulfate in c is a strong electrolyte, hydrogen ions are completely ionized, which is equivalent to strong acid, and aluminum hydroxide is soluble in strong acids and strong bases.

a. Carbon dioxide and sulfur dioxide are not reactive with barium chloride.

b. The hydrogen ions in dilute sulfuric acid and the nitrate ions of Cu(NO3)2 can be formed in the solution to form copper nitrate and can react with nitric acid, that is, the copper powder will dissolve, and "the copper powder is still insoluble" is wrong.

c. Personally, I think it's right.

d. Because of the composition of copper-zinc galvanic cells, the reaction rate will be accelerated.

Selection: None of them produce precipitation.

b: After adding copper nitrate, it is a nitric acid environment, and the copper powder is dissolved.

d: After adding copper sulfate, a galvanic cell is formed, which accelerates the reaction rate.

The reason why they are different types is because in order to distinguish them from the two substances, they have to look at their dissolution equilibrium constants.

If it is a different type of substance, such as the conversion of MGF2 to MG(OH)2, you can add a substance containing hydroxide ions, and then check whether there are F ions after the reaction, if there are no fluoride ions, you can judge that MGF2 is more soluble than MG(OH)2.

1) If the temperature of the original CaCO3 decomposition equilibrium system is increased and the volume of the reaction vessel is reduced, the original equilibrium: dThe direction of the balance movement could not be determined.

Explanation: The higher the temperature, the greater the pressure, indicating that the temperature is rising, and the equilibrium is moving in the positive picoland, and the reaction is endothermic in the positive direction. The heating equilibrium moves in the forward direction, and the pressurized equilibrium moves in the opposite direction.

When the temperature is raised to a certain temperature and then pressurized, the result of the equilibrium movement must be the equilibrium pressure when the pressure returns to that temperature.

2) In a closed container that cannot exchange heat with the outside world, a sufficient amount of CaCO3 establishes a decomposition equilibrium at 850, and if the volume of the sensitive container is doubled, the temperature in the container will decrease when the combustion equilibrium is re-reached. The pressure inside the container will be less than when equilibrium. Rationale:

Decompression, the equilibrium moves in the forward direction, because the positive reaction is an endothermic reaction, and the device is an adiabatic device, the temperature of the system is reduced.

I have some more useful information about the history of Chinese and English.,It's some analysis and classification or something.,Former senior high school teacher ps:Someone, please don't plagiarize my answers.,Please come up with real talent.,Thank you.。 I am an Anhui 08 candidate.

k ca na mg al zn fe sn pb （h） cu hg ag pt au

From left to right it is getting less and less lively. This is the order of metal liveliness, with priority precipitating the least lively.

Others refer to this

1. B Silver ions have the strongest oxidation and react first, iron produces -2 iron ions first, and copper ions cannot oxidize ferrous ions after silver precipitation.

2. D The oxidation of iron ions is stronger than that of hydrogen ions, and the iron is replaced first, and the color of the solution becomes lighter, because magnesium ions have no color.

3. After the reaction of b a hydrochloric acid and sodium metaaluminate, the remaining sodium metaaluminate reacts with ammonium chloride to produce aluminum hydroxide precipitation.

c. Sodium bicarbonate and sodium hydroxide react to form sodium carbonate, and then form calcium carbonate precipitate.

d Barium hydroxide has a surplus in the reaction with nitric acid, and after the reaction with aluminum chloride, the aluminum chloride is excessive, and the resulting product is aluminum hydroxide precipitation.

4. d There is a precipitation of carbonate production.

5. A This is based on the principle of adsorption.

6. Saturated sodium chloride crystal solution.

7. The conditions are insufficient.

8. NH3=1 2N2+3 2H3 Let the decomposition x volume become a+x=b x=b-a, then the remaining ammonia is a-(b-a) =2a-b

9. C Generate lead sulfite precipitation.

10. If b contains (H2O)2, then it has more mass than it does not.

The weighed substance absorbs water.

14. The condition is incomplete: NH3 + ALCL + H2O=AL(OH)3+NH4Cl AL(OH)3+NH3=NH4ALO2+H2O self-balancing.

Among the types of organic matter learned in high school, only carboxylic acid can react with sodium bicarbonate to form carbon dioxide, carboxylic acid has the property of inorganic acid, that is, hydrogen ions can be ionized in solution, a carboxyl group can ionize a hydrogen ion, and a hydrogen ion can react with sodium bicarbonate to form 1mol of carbon dioxide. Starting from the most familiar carboxylic acid, that is, acetic acid, one mol of acetic acid reacts with sodium bicarbonate to form one mol of carbon dioxide (that is, under the standard condition, that is, one mol of carbon dioxide is released by a carboxyl reaction (that is, under the standard condition, 1molx can react with a sufficient amount of sodium bicarbonate solution to release CO2 (standard condition), that is, there must be 2 hydrogen ions that react with sodium bicarbonate. So x definitely contains 2 carboxyl groups.

According to the general formula of dibasic carboxylic acid is CNH2N-2O4, it can be concluded that the answer is D.

h+ +hco3- =co2↑+h2o

The title says that 1mol of X reacts with NaHCO3, if you want to generate 2mol of carbon dioxide, according to the ion equation, you need 2mol of hydrogen ions to ionize and react with bicarbonate, but X substance is only 1mol, so X must be a dibasic acid, so look at the options, since it is set to be a dibasic acid, it means that there will be two carboxylic acids (-cooh), after fixing the two carboxylic acids, only the d option can draw the correct chemical formula, so choose D

Because a carboxyl group is combined with a bicarbonate group to form 1mol of carbon dioxide, 2mol of carbon dioxide is required to form a dibasic acid.

There is no fifth question, only the ninth question.

n(nh3)=v/

n(e-)=n,nh3->no,transfer 5 electrons,reaction n(nh3)n5

na＝(n/5)/（v/

Therefore, choose D.

n=v／

Ammonia catalytic oxidation: 4NH3 5O2 4NO 6H2O) one mole n transfers 5 electrons, so divide the number of transferred electrons by 5 to be equal to the number of moles.

n＝n／5d

Answer: baThe pressure does not change with the movement of the equilibrium, bThe concentration of iodine vapor changes with the shift in equilibrium, cThe concentration of each component is equal, which may be instantaneous, which does not mean that it is unchanged.

d.The same principle is the same as C.

3cu+8h+ +2no3- ==3cu2+ +2no+4h2o

According to the conditions in the question:

The amount of substance of copper =

The amount of no3- substance =

The amount of matter of H+ = (

According to the reaction formula, it can be obtained:

Copper can be dissolved in its entirety.

So the concentration of copper ions =

1. 8h+ +3cu +2no3- =3cu2+ +2 no +4h2o 2.From the above equation, it can be seen that copper is the first to be consumed, and sulfuric acid only provides hydrogen ions and does not participate in the reaction!

So the concentration of copper ions is: mol;