How to distinguish ionic compounds from covalent compounds 10

The distinction between ionic compounds and covalent compounds is very ambiguous if it is distinguished by definition, and I think it is possible to make a simple distinction in this way. Ionic compounds are compounds that exist between 1. active metals (referring to the metallic elements of the first and second main groups) and active non-metallic elements (referring to the elements of the sixth and seventh main groups). 2. Compounds formed between metal elements and acid ions.

Acid ions such as sulfuric acid ions, nitric acid ions, carbonic acid ions, etc.) 3, between ammonium ions (NH4+) and acid ions, or between ammonium ions and non-metallic elements, covalent compounds exist between non-metallic elements, for compounds formed by two elements. If there is a non-polar covalent bond between the same non-metallic elements, if there is a polar covalent bond formed between different elements, they are all covalent compounds.

By definition:

There must be anions and cations in ionic compounds, and of course there must be ionic bonds (which can also be made up of covalent bonds). There are no ions in the covalent compound, only covalent bonds (no ionic bonds can appear).

From the point of view of properties: ionic compounds can conduct electricity in the molten state, whereas covalent compounds cannot conduct electricity in the molten state.

From the point of view of elemental composition: compounds containing active metal elements or ammonium are generally ionic compounds (except for aluminum chloride, ferric chloride, copper chloride, aluminum hydroxide, iron hydroxide, copper hydroxide, etc.). Other compounds are generally covalent.

There are covalent compounds that share electron pairs, and those that do not have ionic compounds... That is to say, those that have electrons transferred are ionic compounds, and those without electron transfer are covalent compounds.

Any compound that has an ionic bond is an ionic compound, even if it also includes a covalent bond.

A covalent compound is a compound that has only covalent bonds and no ionic bonds.

Of course, this is a simple way to tell the difference, but it's very practical.

Distinguish between usable melting point, conductivity, etc. in reality. Ionic compounds that have a high melting point and can conduct electricity in the molten state.

The distinction between ionic and covalent compounds is described below:

1. Covalent compounds occur between non-metal atoms, while ionic compounds occur between typical non-metal atoms and typical metal atoms.

2. Covalent compounds form a stable structure by sharing electron pairs, which forms a whole, and ionic compounds are stacked of ions at room temperature and pressure, without individual molecules. (Molecules are present only in the vapor state).

3. The molecules of covalent compounds have a small gravitational attraction to each other, so they are often easy to diffuse and form gases at room temperature and pressure, while ionic compounds are attracted to each other by many ions with different charges with electrostatic attraction, and the gravitational force is large, so they often form solids at room temperature and pressure.

Ionic compounds are connected by ionic bonds and have no independent structure, and are mostly spatial network structures, such as sodium chloride. Hard and brittle, easy to stratify, and has a high melting and boiling point.

Covalent compounds: Molecular crystals: connected by intermolecular forces (the inside of the molecule is connected by covalent bonds), has a molecular structure, and generally has a relatively low melting and boiling point.

Atomic crystals: connected by covalent bonds, hard, high melting and boiling point The difference is: ionic compounds are all electrolytes, and can conduct electricity in both aqueous solution and molten state Covalent compounds are not all electrolytes, and if they are electrolytes, they cannot conduct electricity in the molten state.

1. Electrical conductivity: ionic compounds are electrolytes, and they can conduct electricity in both aqueous solution and molten state; Covalent compounds are not all electrolytes, and if they are electrolytes, they cannot conduct electricity in the molten state.

2. Molecular crystals and atomic crystals are both covalent compounds. In addition, the gravitational force of molecular crystals is small with each other, so they are often easy to diffuse at room temperature and pressure, forming gas; The ionic compounds are caused by many ions with different charges attracted to each other by electrostatic attraction, and the gravitational force is large, so they often form solids at room temperature and pressure, with greater hardness, brittleness, difficult compression, and difficult to volatilize. Atomic crystals are also usually solid.

3. The force of destruction during melting: ionic compounds must break ionic bonds, and may break covalent bonds (such as sodium bicarbonate), covalent compounds generally do not break covalent bonds, and very few break covalent bonds (SiO2).

4. Melting and boiling point: ionic compounds are higher, covalent compounds are generally lower, and a few are very high (such as SiO2).

1. The composition is different.

Ionic compounds: Compounds composed of cations and anions.

Covalent compounds: Compound molecules composed of atoms that share electron pairs.

2. The melting point and boiling point are different.

Generally speaking, ionic compounds have higher melting and boiling points, greater hardness, brittleness, difficult compression, and difficult volatilization.

Covalent compoundsMost covalent compounds have lower melting and boiling points and less hardness when they are in a solid state.

Ionic compounds are compounds composed of cations and anions, usually composed of metal ions and non-metal ions, while covalent compounds are different, usually composed of two non-metal ions, most of them include hydrogen ions (so that a part of the compound is positively charged, and a part of the negatively charged is attracted to each other) You just need to grasp that ionic compounds are composed of cations and anions, and covalent compounds are different, usually composed of two non-metal ions, most of them include hydrogen ions.