Is there a chemistry master to help me, a chemistry master to help?

There's a lot of pasting upstairs, so I'll talk about it briefly.

I'm a junior in high school, so I'll use the theories I learned in high school to explain qualitatively.

First of all, to correct the landlord's point of view, the relationship between the structure of matter and color belongs to the category of physics.

The movement of electrons inside an atom can be vividly divided into two states, one is the ground state, which is the state of low energy. After receiving the energy of the outside world, the electrons in the ground state are excited to a higher energy orbit and become the excited state, that is, the high-energy state, because the electrons in the excited state are unstable, it will still release various energies it absorbs from the outside world in the form of light energy. Because different atoms and different electrons require different energy from the ground state to the excited state, when they are released, they will also release photons with different energy, which is manifested by their different frequencies, and their macroscopic characteristics are that they emit light of different colors, so there will be substances without colors.

In short, the structure of matter, as an internal factor, determines the energy required for the transition of electrons, and also determines the color of the light corresponding to the energy emitted.

The internal color of matter is the color produced due to the spectrum diffracted by the orbital atom transitions.

The reason for the color displayed by matter is that the energy emitted by the electron transition is radiated in the form of electromagnetic waves. It's a matter of physics.

It doesn't seem to matter, the internal structure has to do with its nature.

No. It is only related to the effect of the electron shell after he is exposed to light.

No. Probably it has something to do with the state of matter.

Probably it has something to do with the state of matter.

It's hard to say what you say in theory, but it's hard to say what it is.

Here's how:

1.Prepare a complexing solution of i2 and starch (a certain concentration, must be accurate), take the standard solution and sweep the maximum absorption peak on the photometer.

2.Take the standard solution for dilution; Prepare a solution of 1 5, 1 25, 1 75, 1 150, 1 300 (you can choose the dilution factor according to your needs).

3.Set the spectrophotometer at the wavelength where the absorption is maximum.

4.Absorption is determined at this wavelength for standard solutions of different concentrations5Make a working curve of concentration vs. absorption (A=ABC)6, and then measure the absorption of the complex solution of iodine and starch remaining from your above experiment at this wavelength.7 The corresponding concentration is found (or calculated) by the working curve.

At the end of the experiment, I have a question, is the complex of iodine and starch stable? How much I2 or starch does it affect absorption? , which solves the above doubts, if there is no impact.

This method is reliable.

Hello Principle of calibration of formaldehyde solution (iodometry) :

In the formaldehyde solution, after adding lye to make the solution alkaline, add a certain amount of excess iodine standard solution, and the formaldehyde is oxidized

hcho + i2 + 3naoh = hcoona + 2nai + 2h2o

Leave for 5 minutes, after the reaction is complete, acidify the solution with hydrochloric acid or sulfuric acid, use starch as an indicator, and titrate the excess I2 with Na2S2O3 standard solution

i2 + 2na2s2o3 = 2nai + na2s4o6 content is about that, just add details

Solution: 2a(g)+3b(g)=xc(g)+4d(g)x4

Solution: x=2

Therefore, when the answer is to solve a question such as b, it is only necessary to convert all the products into reactants. i.e. what is called the equivalent equilibrium upstairs).

18.b PKA and buffer ratio of weak acid 19 c．hco3-

20.D 500ml contains HAC and NAAC21 B, T=

22 B, C (graphite) + O2 (g) = CO2 (g) 23 D, Cl2 (L).

24 a, heat absorption 80 j

Formula used:

Quantity of matter = mass molar mass.

The amount concentration of the substance = the amount of the substance and the volume of the solution.

Mass = Quantity of substance * Molar mass.

80GNOH is dissolved in H2O, prepared into 1L solution, and the amount concentration of the substance is solved: 80g NaOH The amount of the substance = 80 40 = 2mol, so the amount of NaOH solution The concentration of the substance = 2 1 = 2mol L To prepare the NaCl solution, how many grams of NaCl need to be weighed?

Solution: The amount of NaCl substance needed = 2 * = 1mol so the mass of NaCl needs to be weighed = * 1 =