High School Chemistry Please speak 4, 5, 6 questions

Since questions 1, 2, and 3 don't need to be talked about, it means that you have analyzed what exactly the 5 substances are.

a：na2co3 b：ba(oh)2 c：hcl d：agno3 e：al2(so4)3

4) C is hydrochloric acid, a strong electrolyte. pH = 4, then POH = 10, a strong electrolyte from the foreign and added to the solution inhibits the ionization of water. When water is ionized, it is:

H2O<==>OH- +H+, since OH=10 -10, then H+ ionized by water is equal to OH-, so it is also 10 -10

The acidity of the aluminum sulfate solution is due to the hydrolysis of aluminum ions, so the H+ produced by the ionization of water is 10 -4

The ratio of the two, note that it is not a ratio! Yes 10 -4:10- 10=10 6:1 (the answer should be written like this!) ）

Hydrochloric acid with pH=4 and acetic acid with pH=4 are mixed, and the ionization degree of acetic acid remains unchanged!!

It is not that strong acids in the usual sense of our understanding inhibit the ionization of weak acids, and such a conclusion is that the principle of Le Châteale is not well understood!

hac<==>ac- +h+

To reverse the equilibrium, the concentration of H+ added is higher than the concentration of H+ in the current acetic acid solution.

The problem is that you are given hydrochloric acid and acetic acid, both with a pH of 4, that is, the H+ concentration is equal for both. The H+ of hydrochloric acid solution is not higher than that of acetic acid, how can the equilibrium move?

5) The amount of hydrochloric acid and silver nitrate is mixed to obtain a nitric acid solution.

Electrolysis of nitric acid is the electrolysis of water, and electrolysis of water is the anode of oxygen and the cathode of hydrogen. Moreover, with inert electrolysis, oxygen and nitric acid will not corrode the electrode. Then the mass of the yin and yang electrodes will not change.

By electrolysis of water, the volume of water decreases, and there are still so many hydrogen ions. So the concentration of H+ increases and the pH decreases.

6) The amount of nitric acid in 5 is too simple for this, calculate it yourself! ）。Its concentration is dilute nitric acid (it is generally believed that more than 8mol l is concentrated nitric acid, but you don't need to remember this.) Anyway, it's low enough, it's definitely thin), so the reduction product is no

3fe+8hno3==3fe(no3)3+2no↑+4h2o

Iron powder is sufficient, so continue the reaction.

2fe3+ +fe==3fe2+

So the Fe3+ produced is, and then these trivalent irons can also be dissolved in iron.

Total. Convert to mass: (

The answer given in the sixth question on the Internet is that iron powder dissolved by ferric ions is not counted. As the title says, adding a sufficient amount of iron powder indicates that there is an excess of iron. So that last step is also considered.

The network "1-to-1" Q&A is convenient and fast, you can try it. Primary and Secondary Education Network.

NaHCO3---CO2 According to the equation correspondence, the column proportional formula is obtained: vm=mv m

m vmm v

B is saturated sodium bicarbonate, because CO2 is insoluble in saturated sodium bicarbonate solution, so that the solution can be discharged smoothly without considering the amount of dissolved CO2.

Just free. The previous element inference process is sent to your q. d is aluminum, so lidh4 is lialh4

alh4-, to judge its three-dimensional configuration, is to judge its hybridization type. The outer shell of aluminum has 3 valence electrons, plus 4 hydrogen, plus a negatively charged electron, for a total of 8, 8 electrons require 4 orbitals. Hence sp3 hybridization. Tetrahedral structure, like methane.

In the acetic acid molecule, the methyl carbon is sp3 hybrid, and the carboxyl carbon is sp2 hybrid.

The key is a single bond, and the key is a double bond.

Just count 7 keys, 1 key, which is the one with the thick line. In the future, if you are asked to count the keys, you will draw a diagram, a single key is all, a double key is a yes, and a triple key, one is two yes. That's it.

The coordination number in an ionic crystal refers to the number of heteroelectric ions that are closest to an ion. Counting, the oxygen closest to a magnesium is up, down, left and right, front and back, a total of 6.

The previous question asked about density, but now the side length is calculated in reverse, and the side length is calculated as volume. The density of the unit cell is not fundamentally different from other density algorithms. It's the mass volume = density.

The black dot is magnesium, and the white circle is oxygen. Magnesium is on the edge and is shared by 4 unit cells, so it takes 1 4 and 1 in the center.

12 edges 1 4 + 1 = 4 mg.

Oxygen at vertices and surfaces, 8 vertices, 6 faces, 8 1 8 + 6 1 2 = 4

A unit cell has 4 magnesium oxides, one magnesium oxide is 40 na grams, and 4 is 160 nano grams.

160 na side length =a

Side length = 3 160 (na·a).

According to the conservation of charge, the solution satisfies HCO-+OH-=NA++H+, and now the title tells you NA+=HCOo-=BMOL L, which means H+=OH-, so there is H+=10-7mol L

The ionization equation hcooh=h++hcoo-, the material is conserved, the hcooh of amol ionizes the hcoo- of bmol, and the remaining hcooh is a-b, so k=h+*hcoo- hcooh=b*10-7 (a-b).

2H2+4OH--4E=4H2O, O2+2H2O+4E-=4OH-, the electrode reaction is added, less than OH- and 2H2O, the total reaction is 2H2+O2=2H2O, the total reaction is the sum of the electrode reaction, the electrode reaction is the separation of the total reaction, and the split into oxidation reaction and reduction reaction is the electrode reaction. For example, galvanic battery, the positive electrode is to get electrons to undergo a reduction reaction, the negative electrode is to lose electrons, redox ,,,1, according to the total reaction equation, the negative electrode material is pb, pb loses electrons, the positive electrode is to get electrons, the positive electrode is pbo2,2, the positive electrode reaction pbo2 + 4H++SO42-+2E-=PBSO4 + 2H2O, negative reaction: PB+SO42--2E-=PBSO4,3, according to the positive reaction equation, consumption, NH+=, transfer electrons.

The amount of the substance of al is:

Al is transformed from elemental to ionic Al3+ electron transfer.

So the number of electrons transferred is na=

What's wrong with this.

Al, isn't that it, electron?

To clarify the reason for the balance movement of 10 min and 14 min, it can be inferred from the image that CO is reduced at 10 min and pressurized at 14 min, so the concentration of CO is C5-6> C2-3> C12-13 (sharp).

3) Just look at the table, the lower the first ionization energy, the easier it is to become a cation.

4) To [Pauling's empirical law of acid and base], write oxygenated acid in the form of mom(OH)n, m>=2 is a strong acid, m=0 is a weak acid, and it can be determined that H5IO55) I-I bonds have two, that is, two bonds, and 5 electrons, and one electron is obtained, a total of 3 lone pairs of electrons.