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Covalent vs Hydrogen Bond Strength
On the strength of covalent bonds and hydrogen bonds
The genus of chemical bonds, covalent bonds and hydrogen bonds are the authors. Covalent bonds are bonds between atoms that are bound by shared electron pairs. When they form bonds, each atom produces electrons and gathers them in order to achieve a stable state. The strength of this bond is due to the electromagnetic attraction between the electron pair and the atomic nucleus. For example, in methane ($CH_ {4} $), carbon and hydrogen are connected by a covalent bond. The outer layer of the carbon atom has four electrons, and the hydrogen atom each has one electron. The two share an electron pair and form a stable structure. This bond energy is quite high, and it takes a lot of energy to break, so the covalent bond substances have a high melting point and a high boiling point. Because they want to break the bond and cause molecular separation, it is necessary to have a high energy.
As for hydrogen bonding, it is actually a special interaction between molecules or within molecules. The cause is that after the hydrogen atom is connected to the electronegative atoms (such as nitrogen, oxygen, fluorine), the electron cloud of hydrogen is pulled away, so that the hydrogen is positively charged, and then it is attracted to the lone pair of electrons of the electronegative atoms in the adjacent molecules to form a bond. Take water as an example, the hydrogen in the water molecule is connected to the oxygen, and the hydrogen is positive. The oxygen in the adjacent water molecule has a lone pair of electrons, and the two attract to form a hydrogen bond. Although hydrogen bonds also have the function of maintaining the molecular structure, they are much weaker than covalent bonds. Looking at the physical properties of water, it can be seen that the melting point and boiling point of water are not very high, which is far from the diamond composed of covalent bonds. The force of the edge hydrogen bond is just a weak electrostatic attraction between molecules, which is not the same as the strong interaction of the electron pair of the covalent bond.
In summary, the strength of the covalent bond far exceeds that of the hydrogen bond. Covalent bonds act strongly with electron pairs to build a stable foundation for molecules; although hydrogen bonds have a great influence on the properties of matter, their weak force is different from covalent bonds.
The genus of chemical bonds, covalent bonds and hydrogen bonds are the authors. Covalent bonds are bonds between atoms that are bound by shared electron pairs. When they form bonds, each atom produces electrons and gathers them in order to achieve a stable state. The strength of this bond is due to the electromagnetic attraction between the electron pair and the atomic nucleus. For example, in methane ($CH_ {4} $), carbon and hydrogen are connected by a covalent bond. The outer layer of the carbon atom has four electrons, and the hydrogen atom each has one electron. The two share an electron pair and form a stable structure. This bond energy is quite high, and it takes a lot of energy to break, so the covalent bond substances have a high melting point and a high boiling point. Because they want to break the bond and cause molecular separation, it is necessary to have a high energy.
As for hydrogen bonding, it is actually a special interaction between molecules or within molecules. The cause is that after the hydrogen atom is connected to the electronegative atoms (such as nitrogen, oxygen, fluorine), the electron cloud of hydrogen is pulled away, so that the hydrogen is positively charged, and then it is attracted to the lone pair of electrons of the electronegative atoms in the adjacent molecules to form a bond. Take water as an example, the hydrogen in the water molecule is connected to the oxygen, and the hydrogen is positive. The oxygen in the adjacent water molecule has a lone pair of electrons, and the two attract to form a hydrogen bond. Although hydrogen bonds also have the function of maintaining the molecular structure, they are much weaker than covalent bonds. Looking at the physical properties of water, it can be seen that the melting point and boiling point of water are not very high, which is far from the diamond composed of covalent bonds. The force of the edge hydrogen bond is just a weak electrostatic attraction between molecules, which is not the same as the strong interaction of the electron pair of the covalent bond.
In summary, the strength of the covalent bond far exceeds that of the hydrogen bond. Covalent bonds act strongly with electron pairs to build a stable foundation for molecules; although hydrogen bonds have a great influence on the properties of matter, their weak force is different from covalent bonds.
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