What are the common volatile substances in middle school and high school chemistry?

A]:1Volatile substances are molecular crystals.

- There are four types of crystals: atomic crystals, ionic crystals, molecular crystals, and metal crystals.

- Atomic crystals, ionic crystals, and the interactions between particles in molecular crystals are covalent bonds, ionic bonds, and metal bonds, which are chemical bonds, and strong interactions, which make the bonds between particles very strong, making it difficult for particles to be separated from each other and volatilized.

- The intermolecular interaction in a molecular crystal is an intermolecular force, not a chemical bond, but a weak interaction. This makes it easy for molecules to detach from each other.

2.in molecular crystals.

-The lower the boiling point, the more volatile it is.

- The greater the intermolecular force, the higher the boiling point.

-The magnitude of the intermolecular forces is related to the structural properties of the molecule.

- If the structure is similar, the larger the molecular weight, the greater the intermolecular force, the higher the boiling point, and the more difficult it is to volatilize.

- When there are hydrogen bonds between molecules, the intermolecular force is large, the boiling point is high, and it is difficult to volatilize.

3.Volatile substances.

- Generally refers to a liquid or solid state at room temperature.

- Elemental: BR2, I2

- Oxides: CO2 (dry ice), - Hydrides: NH3 (liquid ammonia), H2O, benzene, gasoline and other hydrocarbons.

- Acids: Hno3 (sulfuric acid is a difficult volatile acid, its boiling point is more than 300 degrees) - a lot of organic matter: ethanol, acetic acid, acetaldehyde, ethyl acetate.

4.Why are organic compounds mostly volatile?

- Because a lot of organic matter is molecular crystals.

5.Is the smell due to volatilization?

- Yes, the nose came into contact with volatile molecules.

6.Why are most salts less volatile?

- Because the salt is all ionic crystals, it is also difficult for you to smell the salt.

Chemistry - Solubility of common substances.

Volatile:

1.First of all, it must be liquid.

2.It is divided into liquid mixtures and liquid purifiers.

Mixture (mainly refers to solution), the method of judging the volatility of the solution is: 1).Most gases are formed by dissolving in water, and the solubility of the gases is saturated or about to be saturated.

For example: ammonia, hydrochloric acid (concentrated volatility is greater than dilute) and so on2）.

The gas reacts with water to form a solution of unstable compounds. For example: sulfurous acid, nitric acid, etc.

3）.More complex mixtures, such as gasoline.

Pure substances (including elemental substances and compounds), elemental: liquid bromine, liquid oxygen, liquid chlorine, etc. Compounds: compounds with low boiling point (liquid), liquid ammonia, formic acid, acetic acid, methyl ether, ether, methanol, ethanol, benzene, carbon tetrachloride, carbon disulfide, acetone, etc.

Most of the common substances with strong volatility are some liquid substances with low boiling points. Such as ethanol, ether, acetone, chloroform, benzene, carbon disulfide, etc. There are also ammonia, concentrated hydrochloric acid, concentrated nitric acid, etc., which are highly volatile.

Volatile organic compounds (VOCs) are a class of organic compounds that exist in the air in the form of vapors at room temperature. The main components of VOCs are: hydrocarbons, halogenated hydrocarbons, oxycarbons and nitrogen hydrocarbons, which include:

Benzene series, organochlorides, Freon series, organic ketones, amines, alcohols, ethers, esters, acids and petroleum hydrocarbon compounds, etc.

All of the above substances are highly volatile.

Common volatile substances are: elemental: BR2, I2; Oxide:

Dry ice; Hydride: liquid ammonia; , water, benzene, gasoline and other hydrocarbons; Acids: HNO3, HCl; Organics:

methanol, ethanol, formic acid, acetic acid, formaldehyde, acetaldehyde, ethyl acetate, etc.;

Answer: Elemental: BR2, I2; Oxide: Dry ice; Hydride: liquid ammonia; , water, benzene, gasoline and other hydrocarbons; Acids: HNO3, HCl; Organic matter: methanol, ethanol, formic acid, acetic acid, formaldehyde, acetaldehyde, ethyl acetate, etc.

Volatile are concentrated nitric acid, concentrated hydrochloric acid, ammonia, hydrosulfuric acid, sulfurous acid, carbonic acid, acetic acid, hydrobromic acid, hydroiodic acid, hydrofluoric acid, alcohol, bromine, and mercury.

Concentrated hydrochloric acid, concentrated nitric acid, ammonia, hydrogen sulfide, acetic acid, alcohol, which are common in high school

Concentrated hydrochloric acid, concentrated ammonia, benzene bromide water.

Alcohol mercury.

Common volatile substances are: elemental: BR2, I2; Oxide:

Dry ice; Hydride: liquid ammonia; , water, benzene, gasoline and other hydrocarbons; Acids: HNO3, HCl; Organics:

methanol, ethanol, formic acid, acetic acid, formaldehyde, acetaldehyde, ethyl acetate, etc.;

Answer: Elemental: BR2, I2; Oxide: Dry ice; Hydride: liquid ammonia; , water, benzene, gasoline and other hydrocarbons; Acids: HNO3, HCl; Organic matter: methanol, ethanol, formic acid, acetic acid, formaldehyde, acetaldehyde, ethyl acetate, etc.