Isn t water a molecular crystal and why does it contain covalent bonds Does intermolecular forces in

Molecular crystals must contain covalent bonds, and molecular crystals are composed of countless identical molecules, which are connected by covalent bonds, and all the molecules are attracted by van der Waals forces to maintain the structure of matter.

Water is a molecular crystal, so it must contain covalent bonds, and each water molecule is attracted to each other by van der Waals force (a force between molecules, not chemical bonds) to form the substance of water. This is also the reason why the chemical properties of water have basically nothing to do with the state of matter, the state of matter is different, but the van der Waals force between molecules has changed, and the molecular spacing has changed, but the water molecules that make up water have not changed. The molecular forces have nothing to do with covalent bonds.

Of course, there are hydrogen and oxygen polar covalent bonds in the water molecule, and there is also an intermolecular force between the water molecule and the water molecule, and this intermolecular force does not exist inside the water molecule. The intermolecular force is the intermolecular force, which does not include or contains covalent bonds, covalent bonds are a type of chemical bonds, and other chemical bonds include hydrogen bonds, coordination bonds, and so on.

To put it simply, the covalent bond is inside the water molecule, and the intermolecular forces are between the water molecules.

A covalent bond is not an intermolecular force and is a chemical bond. There is also a type of chemical bond called ionic bond. Because water only has covalent bonds, it is a covalent compound, (but O2 also has only covalent bonds, but it is not a compound, you can call it a molecule).

As long as it contains one ionic bond, it is called an ionic compound, such as NaCl

The force that connects molecules to molecules is the intermolecular force, but the intermolecular force does not include covalent bonds, and it can be said that it is a force that attracts molecules to molecules. Whereas, a covalent bond is the internal force of the molecule, which is the force that connects the hydrogen atom with the oxygen atom. The simple difference is:

Covalent bonds are intramolecular forces, and intermolecular forces are extramolecular forces.

The covalent bond here refers to the bond between the hydrogen atom and the oxygen atom, regardless of whether the molecule is crystal or not.

Molecular crystals have covalent bonds. There are real molecules in the molecular lattice, and the particles inside the molecules are bound by ionic bonds or covalent wide free bonds. Molecular lattice crystals exhibit low hardness, low melting point, easy sublimation, and are electrical insulators.

Matter is made up of molecules, which are made up of atoms, and with the exception of noble gases, none exist in a monoatomic state, but exist in the form of atoms combined with each other to form molecular grinders or crystals. The chemical properties of a substance mainly depend on the internal structure of the molecule, and in order to better grasp the properties of the substance and its chemical change law, it is necessary to discuss the chemical bond and molecular structure on the basis of studying the atomic structure.

The atoms in the atomic crystal are connected to each other by covalent bonds, forming a spatial network structure. Such as carbon atoms in diamond, silicon atoms and oxygen atoms in silica. That is, there is only one force in the atomic crystal, covalent bonds.

The basic particles in a molecular crystal are molecules. Such as solid carbon dioxide. In crystals, there are chemical bonds (covalent bonds in the inner part of the carbon dioxide molecule) inside the elementary particles (carbon dioxide molecules), and there are weak intermolecular forces (van der Waals forces) between the elementary particles (between carbon dioxide molecules), which determine the hardness, melting point, and boiling point of the molecular crystal.

That's why.

Mistake. Contains covalent bonds, which may have the following conditions:

Ionic compounds containing atomic clusters, such as NaOH and NH4NO3, contain both covalent and ionic bonds, and are ionic compounds.

Atomic crystals, such as diamond, Si, SiO2, contain covalent bonds but are made up of atoms.

Molecular crystals, such as N2, HCl, contain only covalent bonds and are made up of molecules.

First, let's look at the definition of a molecular crystal: a crystal formed by the combination of van der Waals forces between molecules. The melting and boiling points are lower and the hardness is less. For example, dry ice (solid CO2), ice, sulfur, iodine, white phosphorus, etc.

The molecular crystals composed of noble gas molecules do not contain covalent bonds. The intermolecular interaction is van der Waals force rather than covalent bonds.

Atomic crystals contain covalent bonds!

This is my humble opinion, and I hope to point out the shortcomings!

Wrong. Most molecular crystals have covalent bonds, but there are also very few that do not have chemical bonds. Such as noble gases.

It's not noble gases, there isn't.

It's not a noble gas, it's a monoatomic molecule, there is no covalent bond, only one atom is covalent, and who is covalent?

Atomic crystals all have covalent bonds, and molecular crystals do not necessarily have covalent bonds. In molecular crystals, the molecule itself may be polyatomic molecules, it may be monoatomic molecules, for example, noble gases are monoatomic molecules, and the crystals formed contain only van der Waals forces and no covalent bonds.

Atomic crystals are non-conductive, insoluble in any solvents, and chemically stable. The particles that make up the crystal are atoms, the interaction between atoms is covalent bonds, the covalent bonds are firmly bonded, the melting and boiling points of atomic crystals are high, the hardness is large, and they are insoluble in general solvents, most of the atomic crystals are insulators, and some such as silicon, germanium, etc. are excellent semiconductor materials.

There is no molecule in the atomic crystal, the chemical formula is used to express the composition of the substance, the chemical formula of the element is directly represented by the element symbol, and the atomic crystal composed of two or more elements is written according to the abbreviated ratio of the number of each atom.

That's right. The intermolecular forces are small and constitute molecular crystals, but allow covalent bonds to exist within the molecule.

In atomic crystals, there are covalent bonds between atoms and atoms, and there is no second force.

The distinction between crystals can be judged by the type of force between the particles.

Diagram of covalent bonds in water: the structural formula is represented by **, and the electronic formula is represented by dots.

Covalent bonds differ from ionic bonds in that the atoms that enter the covalent bonds do not show an outward charge because they do not gain or lose electrons. Covalent bonds are stronger than hydrogen bonds and are not much worse than ionic bonds or sometimes even stronger than ionic bonds. The essence is the formation of shared electron pairs between atoms.

It is generally believed that when the electronegativity difference between the two elements is greater than that, it forms an ionic bond; When it is less than, it becomes a covalent bond.

Saturation. In the process of covalent bond formation, because the number of unpaired electrons that each protogenzi can provide is certain, one unpaired electron of an atom can not be paired with other electrons after being paired with the unpaired electrons of other atoms, that is, the total number of covalent bonds that can be formed by each atom is a certain state, which is the saturation of covalent bonds. The saturation of covalent bonds determines the number of atoms that bind to each other when forming molecules, which is one of the internal reasons for the law of definite proportion.

The above content reference: Encyclopedia - Covalent Bond.