What causes the H bonds in water molecules to last only 10^-11 sec?

[scientiavore]

I have thought of two possible explanations:

a) Energy required to break H bonds = Energy released when H bonds form.
There is a "constant" equilibrium in the system, meaning, some water molecules form H bonds, releasing energy to the environment which causes other water molecules to loose their H bonds, and this could on forever if isolated.

b) The H bonds last so little because the e- density in the water molecules change, the partially charged zones of the molecule are not constant and they change over time breaking the H bonds between the water molecules.

Which one is correct(if any)?

 

[Kushal]

i would suggest that it is because the water molecules are constantly moving around because they possesses kinetic energy.

 

[Blueshift5]

Both explanations have some validity in explaining the short lifespan of H bonds in water molecules. However, the most accurate explanation is likely a combination of both factors.

The first explanation, based on energy equilibrium, is correct in that the energy required to break H bonds is indeed similar to the energy released when they form. This means that the bonds are relatively weak and can easily be broken and reformed. However, this explanation does not take into account the constant movement and rearrangement of water molecules in solution.

The second explanation, based on the changing electron density of water molecules, is also valid. As water molecules move and interact with each other, the distribution of electrons within the molecule can change, leading to a weakening or breaking of H bonds. This is due to the polar nature of water and the constant movement of its molecules.

In reality, the short lifespan of H bonds in water molecules is a result of both factors. The weak nature of the bonds and the constant movement and rearrangement of water molecules work together to ensure that H bonds only last for a very short period of time (10^-11 seconds). This allows for the dynamic nature of water and its ability to form and break bonds, which is essential for many biological processes.