A bunch of chemistry problems cell related .

1) The cation gains electrons and becomes elemental or valence cations, and the anions lose electrons and become elemental.

2) Yes, but the concentration of metal ions to be plated is reduced, for example, copper sulfate solution for copper plating will reduce the concentration of copper ions and form sulfuric acid.

3) Mechanism: galvanic batteries have spontaneous redox reactions to convert chemical energy into electrical energy, which is equivalent to batteries.

The electrolytic cell requires an external power supply to convert electrical energy into chemical energy. It is equivalent to using electrical appliances.

Structurally: galvanic cells are divided into positive and negative electrodes, and electrolytic cells are divided into cathodes and cathodes.

4) Yes, otherwise, like blister copper, the copper in it may be free in the solution, and the acid used in the electrolyte is generally electrolyzed water, depending on the situation.

5) In fact, the strength of oxidation determines the discharge sequence of cations, and the strength of reduction determines the discharge sequence of anions. However, for example, the concentration of ferrous ions will determine the discharge sequence, which is an individual case, and iron, cobalt and nickel are generally not examined, so there is no need to explore them.

1. The process by which metal ions get electrons and become elemental.

2. The metal of the anode is to ensure the concentration of metal ions in the electroplating solution.

3. One discharge, one electricity.

4. Definitely, with salt solution.

5. When this is done, the question will give information, just remember it.

1. Ion discharge refers to the process of ion gaining or losing electrons, and metal ion discharge is the process of obtaining electrons.

2. The anode: The anode, the coated metal, is used to ensure the concentration of the metal ions in the electroplating solution, because the coated metal on the plated parts is obtained by the discharge of the coated metal ions.

3. The galvanic cell is a device that converts chemical energy into electrical energy according to the principle of redox reaction, while the electrolytic cell is a device that converts electrical energy into chemical energy (redox reaction still occurs).

4. The electrolytic refining of metals is the same as the principle of electroplating, and the electrolyte used for electrolytic refining of metals must have the metal ions in them, without acid. However, other electrolytes can be acid.

5. The discharge of metal ions can be judged by the order of metal activities, or according to the metallicity of the elements in the periodic table.

1.In an electrolytic cell, metal ions gain electrons at the cathode to become elemental metals or lower their valence.

2.In most electroplating processes, the metal ions in the plating solution are provided by the anodic dissolution, such as zinc plating, copper plating, nickel plating, etc., but there are also insoluble anodes, and the metal ions are only provided by the plating solution, such as chrome plating. In some cases, insoluble anodes are used specifically for the sake of necessity, such as stainless steel plating, and in order to overcome the problem that the rapid increase of nickel ions in the original pre-plating solution cannot be controlled, a pre-plating solution that can use insoluble anodes is invented.

3.The biggest difference is that the electrode reaction power is different, the galvanic cell is spontaneously emitted, and the electrons can spontaneously flow from the negative pole to the positive pole to form an electric current; Electrolytic cells are electrode reactions carried out under an applied electric field, such as electroplating and electrolytic refining.

4.Electrolytic refining of metals must be done with electrolytes containing the metal ions, however, these metal ions can be added in advance or slowly added by anodic dissolution. Electrolytes are usually acidic, some are more acidic, such as electrolytic zinc, copper, etc., and some are weaker, such as electrolytic nickel.

5.The order of activity of metals is still useful, it is the basic theory. Sometimes there is a discrepancy with the order, which is caused by the easy oxidation or passivation of some metal surfaces, such as nickel, which ranks ahead of hydrogen in the electrochemical sequence, but the non-oxidizing acid reaction is very weak, because there is a passivation film on the surface.

Cell electrode discharge sequence.

Cathode: cation discharge, strong electronic ability to discharge first.

ag+＞hg2+＞fe3+＞cu2+＞h+＞pb2+＞sn2+＞fe2+＞zn2+> h+(h2o)>al3+>mg2+>na+>ca+>k+

Anode: anion discharge or electrode discharge, strong electron loss ability first discharge If the anode is a reactive metal (before the metal activity order table AG), the anion in the solution is not discharged, but the electrode material loses electrons. If the anode is inert (PT, Au, graphite), the discharge sequence is as follows:

S2 i br Cl oh oxynate ion H+ is in front of Na+, so H+ gets electrons to produce hydrogen.

If it is an inert electrode material and is an aqueous solution of electrolysis of Cuci2 and NaCl, then there are cations in the solution: sodium ions, hydrogen ions, copper ions, anions: chloride ions, hydroxide ions, and the electrolysis should be divided into 3 stages

1. Cathode: copper ion discharge to generate elemental copper, anode: chloride ion discharge to generate chlorine gas, equivalent to electrolytic copper chloride.

2. Cathode hydrogen ion discharge to generate hydrogen, anode chloride ion discharge to generate chlorine, equivalent to electrolysis of sodium chloride solution, 3. Cathode hydrogen ion discharge to generate hydrogen, anode hydroxide ion discharge to generate water and oxygen, equivalent to electrolysis of water.

The most developed ones are indeed copper and chlorine.

1 All hydroxide ions and hydrogen ion movement have an effect. If it doesn't move, where does the ion discharge come from? Ions move in order to discharge.

Electrolysis of water, hydrogen ions on the cathode get electrons to generate hydrogen, so the concentration of hydrogen ions near the cathode decreases, relatively speaking, the concentration of hydroxide increases, so the pH increases, in the same way, the hydroxide ions on the anode lose electrons to produce water and oxygen, so the concentration of hydroxide ions near the anode decreases, relatively speaking, the concentration of hydrogen ions increases, so the pH decreases.

The cation moves towards the cathode, and the anion moves towards the anode.

Not necessarily, when electrolyzing CuCl2 (regardless of the reaction between Cl2 and H2O), there will be no effect, whether the pH changes, mainly depends on whether H+ or OH is involved in the electrolysis of water, the cation moves to the cathode, H+ moves to the cathode, becomes H2 overflow, and the ionized H+ goes, leaving the cathode OH- so the pH rises.

Knowledge of physics: the direction of the current is from the anode to the cathode, and the electrons are emitted from the cathode like the anode direction.

Answer: Then it means that the electron, that is, the negative charge, is emitted from the cathode, and when it is emitted, the charge of the hydrogen ions is neutralized to produce hydrogen atoms, and the hydrogen atoms are polymerized into hydrogen gas, leaving the hydroxide radical, so the hydroxide radical aggregation is produced at the cathode. So the pH rises.

Probably, it depends.

The hydroxide group loses electrons to produce oxygen, so it moves to the anode, while the cathode discharges hydrogen ions, and the rest is hydroxide, so the pH value becomes larger.

Cu(OH)2, that is, taken apart, is a CuO and an H2O, respectively, 2CuSO4 + 2H2O = 2Cu+ 2H2SO4 + O2 In the process of electrolyzing copper sulfate, only copper is precipitated and oxygen is released, only copper and oxygen are changed before and after electrolysis, and the solution can be restored to its original state by adding Cuo after electrolysis. However, this question prompts that the solution returns to its original state after adding Cu(OH)2, indicating that not only copper sulfate is electrolyzed but also water is electrolyzed during the electrolysis process.

A Cu2+ 2mol electron is an electron, and an O24mol electron is generated, which is an electron.

Are you sure you pick A?

The electrolytic product is copper and oxygen, with a ratio of 1:1, which can be understood as the remaining unelectrolyzed Cu2+ in the Cuo solution, the H+ generated by the reaction, and the Cu(OH)2 added by SO42- that does not participate in the reaction, which can be understood as CuO+H2O, where the amount of H2O is negligible compared with the amount of water in the solution.

That is, the amount of the substance of Cuo that went out is the same as the amount of substance of Cu(OH)2 that is added.

Electrolysis requires electrons.

I think C is the right choice.

I don't know if you have learned the hydrolysis equilibrium, which only works on salts, as mentioned above, the copper sulfate in B is hydrolyzed to produce hydrogen ions, which makes the solution acidic. If you don't learn it, you will learn it later.

An increase in electrode mass indicates metal precipitation, which is only precipitated by Cu.

In the cation, Cu is more likely to be discharged first than the others.

Remember cations: Just remember the metals in the metal activity order table; The more the one that is ranked later in the table of metal activity, the more the ion gets electrons from the solution (note that Fe3 is after Cu2) It's good Do you get it You can follow up. Hope to adopt.

Judgment of electrode products during electrolysis.

Judgment of anode products.

First look at the electrode, if it is an active electrode (before the metal activity sequence table AG), the electrode material loses electrons and the electrode dissolves. In the case of inert electrodes (PT, AU, graphite), then look at the electron-losing ability of the ions in the solution. The anion discharge sequence is as follows:

Judgment of S2-I-Br-Cl-OH-SO42-NO3-F- cathode products.

Directly judged according to the cation discharge sequence, the cation discharge sequence:

AG+ Hg2+ Fe3+ Cu2+ H+ Acid Pb2+ SN2+ Fe2+ Zn2+ (H+) Water Al3+ Mg2+ Na+ Ca+ K+

Because hydrogen has a high precipitation potential, it can be calculated in electrochemistry.

1. Here is the calculation of how much heat is generated when the temperature is raised. It does not mean that the temperature rises and the temperature decreases to extothermic.

2. Because hydrogen ions gain electrons and release hydrogen, the concentration of cathode hydroxide is greater than that of hydrogen ions, and then combined with sodium to generate sodium hydroxide.

3. The refining of copper is an electrolytic reaction, the cathode gains electrons, the anode loses electrons, and there will be iron, zinc and other impurities in the blister copper hung on the anode in addition to copper, and the ionization produces copper ions, and the reduction reaction occurs at the cathode to obtain copper.

4. Because the liveliness of cu is stronger than silver, the popular point is that it will be replaced. . .

5.Aluminum and copper form galvanic cells, which accelerates the chemical reaction of aluminum, which accelerates the oxidation of aluminum, which accelerates rusting, and Did you know that AL reacts with water?