In the leveling effect and the discrimination effect, the weaker the acidity of the solvent, the wea

In short: the more alkaline the solvent, the more acidic the acidic substance cannot be distinguished from it due to the leveling effect, only the strong base. For example, in liquid ammonia, acetic acid and hydrochloric acid are both strongly acidic and completely neutralized.

The more acidic the solvent, the more alkaline substances cannot be distinguished from each other due to the leveling effect, regardless of their strength or weakness, and only strong acids can be distinguished. For example, in anhydrous acetic acid, ammonia and sodium hydroxide are both strong alkaline and completely neutralized.

When the acidity and alkalinity of the solvent are very weak, you can distinguish between strong and weak acidity and strong and weak alkaline, and the difference range is naturally larger. For example, in water, strong acids and weak acids within a certain range, strong alkalis and weak alkalis can be basically distinguished.

It's not easy to answer questions on your phone, I hope it will help you o(o

I don't understand what you're trying to ask......

To distinguish acid, we need to use weak acid, and to distinguish alkali, we need to use weak alkali, and the focus is on "same acidity and alkalinity" and "weak".

For example, to distinguish HCl and H2SO4, it is obviously not possible to use liquid ammonia, water, etc., because these solvents are leveling solvents for the two; Obviously, HCl4 is also not OK, because HCl and H2SO4 are not as acidic as HCl4, and both are almost non-electrolytes in HClO4. Therefore, use a weak acid, such as HAC. In addition, the degree of "weak" acidity of the solvent should also be controlled, when it is too weak, the ionization of HCl and H2SO4 is too high, and the acidity gap is not obvious; If it is too strong, the ionization of HCl and H2SO4 will be too low, and there will be a large error due to the accuracy of the instrument.

The greater the acid effect coefficient, the greater the stability of the complex. This statement is false.

1. The acid effect coefficient is a parameter used to calculate the equilibrium of the complex, which indicates the degree of interaction between the metal ions and the ligand in the complex. However, there is no direct relationship between the acid effect coefficient and the stability of the complex. In complex chemistry, the acid effect coefficient is a very important parameter, which can express the equilibrium formed by Senru complexes, but cannot directly reflect the stability of complexes.

2. In fact, the stability of the complex depends on a number of factors, including the charge, size, valence state and so on of the metal ions. For example, in coordination bonds, if there are characteristics such as large differential electron pairs, multiple bonds, and melting points, then the corresponding complexes will be more permeable and stable than other compounds. In addition, ligand coordination mode, covalent radius, and covered tissue indexes also affect the stability of complex formation.

3. When calculating the acid effect coefficient, we often use the complex formation constant (kf) to describe it, which reflects the stability of the complex formed in the aqueous solution. This degree of stability is related to the acid effect coefficient, but there is no one-to-one correspondence between the two. Therefore, the stability of the complex cannot be judged simply by the size of the acid effect coefficient.

Multiple Applications of Acid Effect Coefficients:

The acid coefficients of effect are a widely used parameter in complex chemistry that describes the intensity of the interaction between metal ions and ligands. The size of this parameter is crucial for the study of the formation and stability of complexes, and the thermodynamic stability assessment of complexes is widely used in many fields, because the process of complex formation and dissociation is related to thermodynamics.

1. Removal of metal pollutants. For example, ferrous sulfide (S2Fe(II)) can precipitate some divalent metal ions such as Cu(II), Zn(II), Hg(II), etc., which has a very important application in wastewater treatment.

2. Spectral analysis. Acid effect coefficients are also frequently used to explain some spectral phenomena. For example, the bonding capacity of natural organic matter to heavy metal ions can be assessed by comparing the acid effect coefficients to determine whether they are present in groundwater.

3. Biomedical applications. Metal-containing catalysts are often used in biomedical applications where the magnitude of the acid response coefficient can affect their toxicity and pharmacological activity, and in these applications, the acid effect factor is commonly used for clump wax evaluation and control.

Answer - Dinitrophenol p-nitrophenol M-nitrophenol Phenol p-Cresol P-methoxydojuphenol.

The nitro group is an electron-pulling group, and the electron effect makes the hydrogen in the phenolic hydroxyl group easy to ionize, and the phenoxy anion generated is also more stable, so it is more acidic. When the nitro group is in the ortho and paraposition, it has both the influence of induction effect and the conjugation effect, and the effect is stronger. In the meta-position, there is only an induction effect, but no conjugation effect, so the effect is weak. The higher the number of nitro groups, the greater the impact.

When the methyl group and the methoxy group are connected to the aromatic ring, they are both electron-pushing groups, which increases the density of the electron cloud around the oxygen atom on the phenolic hydroxyl group, which is difficult to ionize. In addition, the negative charge of the generated phenoxy anion is more concentrated and unstable, so that it is less acidic. It is also due to the ability of the methoxy group to push electrons (the induction effect of the methoxy group is to pull electrons, and the conjugation effect is to push electrons. Qualitatively, the co-moment effect is greater than the induction effect) is greater than the methyl group.

Therefore, p-methoxyphenol is the least acidic. $oxalic acid, malonic acid, chloroacetic acid, acetic acid, phenol.

The carboxyl chlorine atoms are all electron-pulling groups that enhance the acidity of carboxylic acids; The electron-pulling ability of the carboxyl group is greater than that of the chlorine atom, and the acidity increases more. In oxalic acid, the two carboxyl groups were directly linked to each other, and the induction effect was the largest, and the acidity was the strongest. Carboxylic acids are more acidic than phenols. $Trifluoroacetic acid hand sales file benzocough acetic acid phenol ethanol.

Trifluoromethyl is a strong electron-pulling group, and the induction effect makes trifluoroacetic acid the most acidic; The phenyl group is also an electron-pulling group but has less ability to pull electrons. The methyl group in acetic acid is the electron-pushing group, and the electron-pushing induction effect makes it less acidic.

A In the same main group, the non-metallic property of the element decreases with the increase of atomic number, so the non-metallic Cl br i, the stronger the non-metallic non-metal, the stronger the acidity of its most ** oxygenated acid, so acidity: HCO4

hbro4hio4

therefore a error; b In the same main group, the metallicity of the element increases with the increase of atomic number, so the metallicity k na li, the stronger the metallicity of the metal, the stronger the alkalinity of the corresponding base, so the alkalinity is strong: koh naoh lioh, so b is correct;

c In the same period, the non-metallic property of the element increases with the increase of atomic number, so the non-metallic Cl S P, the stronger the non-metallic non-metallic, the stronger the stability of its hydride, so the stability of HCL H2

s ph3 so c is wrong;

d In the same main group, the non-metallicity of the element decreases with the increase of atomic number, so the non-metallic Cl br i, the stronger the non-metallic non-metallic property, the stronger the oxidation of its elemental matter, so the oxidation I2

br2cl2

Therefore D is wrong; Therefore, choose B

a non-metallic cl br i, the stronger the non-metallic nature of the element, the stronger the acidity of the hydrate corresponding to the most ** oxide, so a is wrong;

b metalliness, the stronger the metallicity of the element, the stronger the alkalinity of the hydrate corresponding to the most ** oxide, so b is correct;

c Non-metallic Cl s P, the stronger the non-metallic nature of the element, the stronger the stability of the corresponding hydride, and the error over C;

d non-metallic cl br i, the stronger the non-metallic nature of the element, the stronger the oxidation of the corresponding element, so d is wrong

Therefore, choose B

a non-metallic cl br i, the stronger the non-metallic nature of the element, the stronger the acidity of the hydrate corresponding to the most ** oxide, so a is wrong;

b non-metallic o s se, the stronger the non-metallic nature of the element, the more stable the corresponding hydride, so b is wrong;

c metalliness: k na li, the stronger the metallicity of the element, the stronger the alkalinity of the hydrate corresponding to the most ** oxide, so c is correct;

d non-metallic cl br i, the stronger the non-metallic nature of the element, the stronger the oxidation of the corresponding element, so d is wrong

Therefore, C

A. The stability of gaseous hydride is Hi HBR HCl HF, then the acidity is HI HBR HCl HF, so A is wrong;

B. Due to the non-metallic F Cl Br I, the stability is Hf Hcl Hbr Hi, so B is wrong;

c. The stronger the non-metallic property, the stronger the oxidation of the element, and the non-metallic F Cl br i, then the oxidation is F2 Cl2 br2 i2, so C is wrong;

d. The elemental of halogen elements, the smaller the relative molecular weight, the lower the melting and boiling point, the boiling point is F2 Cl2 Br2 I2, so D is correct;

Therefore, choose D