Shanxian Chemical
SUPPLEMENTS
Strength of Hydrogen Bond
On the strength of hydrogen bonds
There are different opinions on the strength of hydrogen bonds in the world. Either the cloud is weak, which is inferior to the covalent bonds; or the cloud is strong, which is also crucial for the aggregation, dispersion and clutch of molecules.
The essence of hydrogen bonds is that hydrogen particles are between strong dielectronegatives, so this special attractive force is generated. Electronegativity is strong, such as fluorine, oxygen, nitrogen, etc. Hydrogen is connected to it, and the electron cloud is biased towards the electronegative strong, causing the hydrogen to appear slightly positive, so it is attracted by the electronegative strong elsewhere. This is the origin of hydrogen bonds.
As for its strength, it is difficult to generalize. In different systems, the strength of hydrogen bonds varies greatly. Taking water as an example, hydrogen bonds between water molecules give water specific physical properties. Its boiling point is higher than that of its peers, due to the force of hydrogen bonds, which maintains molecules and makes them difficult to disperse. The force of hydrogen bonds, although not as strong as covalent bonds, should not be underestimated, about one-third of covalent bonds.
Looking at organic systems, among alcohols, hydrogen bonds between hydroxyl groups also have considerable force. The boiling point of ethanol is higher than that of ethane, due to hydrogen bonds. However, its strength is slightly different from that of hydrogen bonds between water molecules, or varies depending on molecular structure and environment.
What's more, in biological macromolecules, the effect of hydrogen bonds is even more wonderful. The secondary structure of proteins, alpha-helix and beta-fold, all rely on hydrogen bonds to form them. Although the strength of these hydrogen bonds is not huge, many hydrogen bonds cooperate to stabilize the protein structure and exercise its biological energy.
From this perspective, the strength of hydrogen bonds is not only determined by the electronegativity and atomic spacing of the connected atoms, but also related to the environment and molecular structure. Although their forces are different, they are indispensable to the state and biochemical changes of all things. Therefore, exploring the strength of hydrogen bonds is one of the keys to understanding the mysteries of matter.
There are different opinions on the strength of hydrogen bonds in the world. Either the cloud is weak, which is inferior to the covalent bonds; or the cloud is strong, which is also crucial for the aggregation, dispersion and clutch of molecules.
The essence of hydrogen bonds is that hydrogen particles are between strong dielectronegatives, so this special attractive force is generated. Electronegativity is strong, such as fluorine, oxygen, nitrogen, etc. Hydrogen is connected to it, and the electron cloud is biased towards the electronegative strong, causing the hydrogen to appear slightly positive, so it is attracted by the electronegative strong elsewhere. This is the origin of hydrogen bonds.
As for its strength, it is difficult to generalize. In different systems, the strength of hydrogen bonds varies greatly. Taking water as an example, hydrogen bonds between water molecules give water specific physical properties. Its boiling point is higher than that of its peers, due to the force of hydrogen bonds, which maintains molecules and makes them difficult to disperse. The force of hydrogen bonds, although not as strong as covalent bonds, should not be underestimated, about one-third of covalent bonds.
Looking at organic systems, among alcohols, hydrogen bonds between hydroxyl groups also have considerable force. The boiling point of ethanol is higher than that of ethane, due to hydrogen bonds. However, its strength is slightly different from that of hydrogen bonds between water molecules, or varies depending on molecular structure and environment.
What's more, in biological macromolecules, the effect of hydrogen bonds is even more wonderful. The secondary structure of proteins, alpha-helix and beta-fold, all rely on hydrogen bonds to form them. Although the strength of these hydrogen bonds is not huge, many hydrogen bonds cooperate to stabilize the protein structure and exercise its biological energy.
From this perspective, the strength of hydrogen bonds is not only determined by the electronegativity and atomic spacing of the connected atoms, but also related to the environment and molecular structure. Although their forces are different, they are indispensable to the state and biochemical changes of all things. Therefore, exploring the strength of hydrogen bonds is one of the keys to understanding the mysteries of matter.
Scan to WhatsApp
