Fast!!! Velocity!!! The direction in which the chemical reaction is carried out, the equivalent equi

Most of the dynamic equilibrium is the reaction of gases, so you have to consider three aspects:

1。Temperature, regardless of volume and pressure, whether the temperature decreases or rises during the reaction, the decrease is endothermy, and vice versa, then you consider whether it is a positive reaction or your reaction;

2。volume, the title of the book will generally be: the volume change is to consider the amount of mol generated during the reaction, (your reaction formula 1mol + 3mol = 2mol), it can be seen that the volume decreases when the complete reaction is complete, so in the constant capacity state, the pressure decreases;

3。The pressure is very much according to your reaction formula, as long as this reaction formula is from left to right, then his internal pressure must be reduced.

Summary: When encountering such a problem, you can think like this: constant temperature and constant capacity, the reaction must be related to pressure, constant temperature and constant pressure, the topic must be how the volume will be after the reaction, constant pressure and constant capacity, then you must know, consider the change of temperature.

In the end, I don't know if you can understand it, maybe what I said is not to the point, but you have to be clear: reversible chemical reactions follow the following principles: conservation of matter (that is, chemical balancing) and conservation of energy (that is, exothermic and endothermic of positive and negative reactions), there are gains and losses!

According to the conservation of matter, it can be seen that the state of A and B is exactly the same when the two conditions reach equilibrium, the difference is that A is gradually equilibrium from left to right, and B is gradually equilibrium from right to left.

If the reaction is complete, the change in heat should be.

0--- equilibrium position--- fully reactive (

The change in heat from left to right is known to be a, which is the change in heat from 0 to equilibrium.

The heat change from right to left is b, which is the change in heat that perfectly reacts to the equilibrium state.

So a+b=

Let me explain the d answer.

Acid zinc-manganese dry cell battery.

Negative electrode: zn-2e zn2+

Positive electrode: 2NH4 2E 2NH3 H2

The H2 produced is oxidized by Mno2: H2+2Mno2=Mn2O3+NH3 produced by H2O, which in turn reacts with ZnCl2: Zn2++4NH3=[Zn(NH3)4]2+

The function of starch paste is to increase the migration rate of anions and cations in the two electrodes.

The total reaction formula of the battery: 2Zn+4NH4Cl+4MNO2 [ZN(NH3)4]Cl2+ZNCL2+2MN2O3+2H2O

Manganese dioxide is used as a depolarizing agent.

Hydrogen gas is produced, which adheres to the carbon rods. Due to the large resistance of hydrogen, it occurs when the battery is working"Polarization"--- generates a considerable amount of voltage in the vicinity of the battery, causing the road-end voltage to drop. So manganese dioxide is added to the battery as"Depolarizing agents"）

Alkaline zinc-manganese dry battery in:

Negative electrode reaction Zn+2OH--2E=Zn(OH)2 positive electrode reaction 2mNO2+2H2O+2E=2MnoOH +2OH-total reaction Zn+2mNO2+2H2O=Zn(OH)2+ 2MnoOH manganese dioxide as an oxidant.

The first half of the sentence in C is correct, the second half of the sentence is wrong, and when the switch is turned on, the gas will precipitate from the PT.

zn is the negative pole zn-2e=zn2+

It is right to release gas on the PB.

In Figure A, the iron rod is chemically corroded, and the part near the bottom end is in less contact with oxygen, and the degree of corrosion is lighter, and item A is wrong;

In Figure B, the switch is placed by M on N, Cu-Zn as the positive pole, and the corrosion rate decreases, B pairs;

In Figure C, when the switch is turned on, Zn is used as the negative electrode, and the corrosion rate increases, but the hydrogen is released on the PT, and the C term is wrong.

In Figure D, the reduction reaction of Mno2 occurs when the dry battery is discharged, which reflects the reduction, and the D item is wrong.

Hope it helps.

You got this question wrong, you should have chosen the right one.

In the case of term d, chemical energy is not only converted into heat energy but also into light energy during the combustion process, and hydrogen will have a blue flame when burned in oxygen.

AB error can be judged by endothermic bond exothermic from broken keys, and the C item can be seen from the figure that all the old bonds are broken to form new bonds, which is correct, so C is chosen

I can only say that this question is wrong! You can ask someone.

The ratio of the amount of matter in the kal(so4)2 solution and the ba(oh)2 solution is 2:3, the ionic equation.

2al3+ +3so42- +3ba2+ +6oh-==2al(oh)3 + 3baso4

Put the amount of kal(SO4)2 and BA(OH)2 of the same amount into sufficient water.

al3+ +2so42- +2ba2+ +4oh-=2baso4↓+alo2-+2h2o

Add Ba(OH)2 solution to the alum solution to the SO42- complete precipitate.

3ba2+＋6oh-＋2al3+＋3so4 2-＝3baso4＋2al(oh)3

1 2al3+ +3so42-+ 3ba2+ +6oh- = 2baso4↓+ 2al(oh)3↓

2 3al3+ +3so42-+ 3ba2+ +6oh- = 3baso4↓+ 2alo2- +al(oh)3↓

3 Add Ba(OH)2 solution to alum solution to complete SO42- precipitation.

al3+ +2so42- +2ba2+ +4oh- = 2baso4↓+ alo2- +2h2o

The resulting solution is alkaline.

kal(so4)2+2ba(oh)2=2baso4↓+kalo2+2h2o

At this point, the solute in solution is kalo2

Kalo2 hydrolysis is alkaline.

alo2- +2h2o = al(oh)3 + oh-

The main component of some stones is calcium carbonate, and the water from the eaves drips onto the stones, and the carbon dioxide dissolved in the water can gradually convert calcium carbonate into soluble calcium bicarbonate.

The calcium bicarbonate and magnesium bicarbonate dissolved in tap water decompose in boiling water, releasing carbon dioxide and turning into insoluble calcium carbonate and magnesium carbonate, forming scale.

The third question can be explained by the first one, but when I was learning, I just put CO2 into the clarified lime water, and it will be turbid, and my stepbrother guesses that it will be clear, but it will become turbid again without what you said, and it will become turbid, and it will be repeated.

When CO2 is passed into the clarified lime water, the lime water becomes turbid because of the formation of calcium carbonate precipitation, and the calcium carbonate reacts with carbon dioxide and water to form soluble calcium bicarbonate, so it becomes clear again. This should end up with the reaction equation of the two processes.

Ca(OH)2 + CO2 = CaCO3 (tremor tolerance) + H2O

CaCO3+CO2+H2O=Ca(HCO3)2 (note that when writing, don't forget that there is water to participate in the reaction).

1) h na kf <

2) The chemical bonds that are not broken are peace talks3,5;Ionic bond breaking1,4;Covalent bond destruction evokes stupid touch2,6

3) A, collapse B, C, balance.

18（1）o 2na2o+o2=△=2na2o22)hcl

1) H na kf si "Mo Song n

2) The unbroken key of Huaqiao is 3,5;Ionic bond breaking1,6;Covalent bond destroys Minhui2

3）a、b;c, balance.

18（1）o2- 2na2o+o2=△=2na2o22)hcl