What is the definition of purity? 1. What is the definition of purity?

Pure substance: It is composed of only one substance, has fixed chemical and physical properties, and must be able to write a chemical formula.

Pure: Composed of only one substance. Such as: oxygen, hydrogen, water, CO2

Substances with fixed composition and fixed physical and chemical properties Examples: oxygen, nitrogen, potassium chlorate, etc. are all pure substances.

Example. o2、n2、c、mg、fe、p2o5、fe3o4、mgo、p、h2o……

It is a substance with fixed composition and fixed physical and chemical properties.

Such as: O2, N2, C, MG, Fe, P2O5, Fe3O4, MGO, P, H2O......

It is a substance with fixed composition and fixed physical and chemical properties.

Purity: There is a substance that is composed of substances.

Characteristics: Pure substances have fixed physical and chemical properties.

A pure substance can be expressed by a chemical formula, and a pure substance must be expressed by a chemical formula. Here are some examples:

Oxygen is a pure substance composed of oxygen, a substance, with the chemical formula O2.

It has fixed physical properties: colorless and odorless gas, melting point 183℃。

It has fixed chemical properties: flammability, oxidation.

It can react with carbon to form carbon dioxide.

Reacts with metals to form metal oxides, etc.

The difference between a mixture and a pure substance

1. Macro differences.

Pure matter is composed of only one substance, such as oxygen, water, etc.

A mixture is a substance that is formed by mixing two or more substances. Such as: air, alloys, etc.

2. Different nature and characteristics.

The composition of pure substances, physical code properties and chemical properties are fixed, and there are special chemical symbols.

Mixtures have no fixed properties and composition and cannot be expressed by a chemical formula. Each substance retains its original properties (e.g., there is no fixed melting or boiling point).

3. The molecular composition is different.

Pure matter is made up of particles of the same kind (molecules and atoms.

The substance of the composition.

Mixed tardling is a substance composed of two or more molecules.

4. The elements contained in the sparrow are different.

Pure substances contain one element, such as O2, N2, etc. (elemental) Contains a variety of elements, such as KMno4 (potassium permanganate.

and other compounds. The mixture contains a variety of elements, such as alloys containing one element, and a variety of elements such as O2 and O3; White phosphorus.

and a mixture of red phosphorus.

Definition of pure matter: pure matter is a kind of cracked spike element or a substance composed of a compound, with fixed physical and chemical properties, with a special chemical symbol, can be represented by a chemical formula.

Different forms of pure substances are also pure substances when mixed together, such as ice water and pure water, and the mixture is a substance composed of two or more pure substances (elements or compounds) that have not been chemically synthesized. For example, air, tap water.

Distinguish from mixtures

1. Pure matter is composed of the same substance, it has a certain composition, which can be expressed by a chemical formula, and pure matter has certain properties (such as fixed melting and boiling points).

2. The mixture is made up of different substances, which has no certain composition and cannot be expressed by a chemical formula. The mixture does not have fixed properties, and each substance retains its original properties (e.g., there is no fixed melting and boiling point).

Pure substance refers to a polymer composed of a single substance or a chemical compound, composed of a fixed, fixed physical and chemical properties, with a special chemical symbol, can be expressed by a chemical formula.

The concept of purity

Macro: A substance made up of one component.

Microscopic: Composed of particles of the same kind.

In the real universe, pure matter is only a theoretical state.

It is distinguished from mixtures such as spike rounds

1. Pure matter is composed of the same substance, it has a certain composition, which can be expressed by a chemical formula, and pure matter has certain properties (such as fixed melting and boiling points).

2. The mixture is made of different kinds of slag collapse substances, which has no certain composition and cannot be expressed by a chemical formula. There is no fixed property of mixed Hu matter, and each substance retains its original properties (such as no fixed melting and boiling point).

Connection with the mixture

The connection between the puree and the mixture is reflected in the fact that the mixture is obtained by mixing a variety of pure, and the mixture can be separated into pure.

What are the pure substances?

Water, oxygen, crystal, iron, **, methane, carbon dioxide, ethanol (alcohol), iodine, ozone.

Pure explanation.

1) [pure] without admixture; The purest silk available without additives, substitutes or impurities (2) [clean] Non-polluting; A detailed explanation of pure purity is pure purity. Lao She, "Crescent Moon": The faint light of the moon illuminates this snow half white, and half of it is slightly gray, showing an unimaginable purity.

Ba Jin, "The Fourth Ward": You can make your heart a little purer by reading poetry. ”

Word decomposition Pure Interpretation Pure (pure) úSingle-minded: pure. Pure.

Simplicity. Pure gold. Pure copper.

Purity. Pure. Skilled.

Purity. Silk: "Zi said:

hemp crown, auspicious suspicion chain salute; Today is also pure, thrifty, and I follow the herd's book". Great: Pure (great blessings).

the beauty of character: simplicity. Pure.

Pure thick. Pure tuk. Purity Explanation of Purity Cleanness Clean:

Cleanse. Water purification. Pure Land.

Pure Mind (..)Pure heart;There is no concern in my heart).

Join Temple (Buddhist Temple. Also known as "Jingyu"). Clean.

Clean. The window is bright and sunny. Make it clean:

Net surface. Clean hands (urine and urine). Empty, nothing:

Exhaustive. Pure, pure: net profit. Net worth.