How does the acidity of hydrides change in chemistry within the same main group

How does the acidity of hydrides change in chemistry within the same main group

Elements of the main group of the same period.

Reducibility of gaseous hydrides.

Descend from left to right.

Reason: The number of electron layers from left to right in the same period is the same, and the attraction ability of the outermost electrons is enhanced, so it is oxidized.

Gradually enhanced. When it is atomized with hydrogen.

When hydride is formed, the ability to attract electron pairs is strong, so other atoms will "laborious" to obtain electrons from the non-metallic atom, so that the ability to lose electrons is weak, and the reducibility is weak. So in the final analysis, we only need to look at the reducibility of gaseous hydrides by the electron-gaining ability (i.e., oxidation) of the non-metallic element!

1. Gaseous hydride generally refers to non-metallic hydride, that is, non-metal with its lowest valence.

A gaseous (generally at room temperature and pressure) compounds combined with hydrogen. It should also be noted that the gaseous hydride generally refers to simple hydrides, such as C element corresponds to CH4 instead of C2H4, C2H6, etc., and Si element corresponds to SiH4 instead of Si2H6, etc.

2. In gaseous hydrides of the same periodic element, the bond length of H-R (R is a non-metallic element) decreases gradually, and in the gaseous hydrides of the same main element, the bond length of H-R gradually increases. Chemical properties of gaseous hydrides.

Change law and characteristics (the stronger the non-metallic, the better the stability).

3. Gaseous hydrides of the same periodic elements (from left to right);

It is becoming easier and easier for non-metals to be combined with hydrogen;

The stability of gaseous hydrides gradually increased;

The reducibility of gaseous hydrides gradually decreases.

4. Gaseous hydrides of the same main group elements (from top to bottom);

It is becoming more and more difficult to combine with hydrogen;

The stability of hydrides gradually decreases;

The reducibility of hydrides gradually increases;

Gaseous hydride aqueous solutions become progressively more acidic (e.g., HF

During the same period, from left to right, the hydride stability gradually decreases.

The stronger the non-metallic nature of an element, the greater the stability of its gaseous hydride.

In the same period, left to right, the elemental non-metallic property is enhanced, and the stability of gaseous hydrides is enhanced, such as SiH4HCl>HBR>HI

The higher the relative molecular weight of hydrides of the same main group element, the higher the boiling point, but the hydrogen bonds of NH3, H2O and Hf are higher than those of other elements of the same main group.

x, y, z, w, q are all short-period main group elements, where x is the element with the largest short-period atomic radius, then x is na; X and Y are in the same period, and Y and Z are in the same main group and can be guessed as two common compounds, then Y is the S element and Z is the O element; W can form two simple ions, then W is the H element; The total number of electrons of the q atom is equal to 3 times the number of its electron shells, the atom can only have 2 electron shells, and the number of electrons outside the nucleus is 6, so q is the c element

Element A is carbon and is not the strongest non-metallic element in the short-period hall, and the strongest non-metallic element in the short-period hall roll type is element F, so A is wrong;

The compounds formed by b y and z are sulfur dioxide and sulfur trioxide, both of which are acidic oxides.

C y, z, q and w respectively formed compounds are hydrides, which are hydrosulfide, water, and both, respectively, because there are hydrogen bonds between water molecules, the boiling point is the highest, so c is correct;

The sodium peroxide formed by D DNA and oxygen contains both ionic and covalent bonds, so d is correct, so CD is chosen

It's a mistake in the title, it should be "concentrated H2SO4 shows both oxidation and acidity when transforming the following substances" The valency of S in concentrated sulfuric acid is +6 valence, which has reached the maximum, so it is impossible for concentrated sulfuric acid to show reducing A, concentrated sulfuric acid shows both oxidation and acidity, concentrated sulfuric acid in B, only oxidizes in concentrated sulfuric acid in C, and concentrated sulfuric acid in D only shows acidity.

When determining the concentration of i- in a solution containing i- with a very small concentration of i-, an oscillation reaction can be used for chemical amplification to find the concentration of iodine ions in the original solution The main steps are:

In a neutral solution (, oxidize the i- in the sample to io3- with Cl2 to remove the excess Cl2;

Excess potassium iodide is added to completely convert io3- to I2 under acidic conditions;

After the iodine generated in is completely extracted, it is reduced to i- with hydrazine, and the chemical equation is n2h4+2i2=4i-+n2 +4h+;

Iodine titration is a method to titrate i2 (or dissolved i2, or i2 generated by reaction) in the solution with sodium thiosulfate as the standard solution to determine the content of some substances in the test solution, the ion equation is i2+2=2i-+, and the iodine titration method should be in.

a.Perform b. in a strongly acidic solutionPerformed in a strong alkaline solution.

c.Perform d. in near-neutral solutionAll three solutions can be used in the environment.