Why Does Water Require More Energy to Become a Gas?

[menniandscience]

hello, my question is how come molecule of water, although much lighter than molecule of oxygen, needs much more enegrgy to become a gas and mix in the air? is it the way energy spread or absorbd in the molecule? thank you

 

[Ygggdrasil]

A liquid consists of a collection of many molecules that are losely bound through non-covalent intermolecular bonds. A gas is a collection of many non-interacting molecules. Therefore, going from a liquid to a gas involves breaking those non-covalent bonds between molecules, and the energy required to vaporize a compound is related to the energy of these intermolecular bonds.

Molecular oxygen is a non-polar molecule that interacts with other molecules of oxygen through very weak London dispersion forces. Water molecules, on the other hand, are polar and can interact with other water through hydrogen bonds, a very strong type of intermolecular bond.

Although it is true in general that more massive molecules will have higher boiling points, it has nothing to do with the molecule's weight. Rather, larger molecules will experience larger dispersion forces that keep the molecules together.

 

[quicknote]

Water requires more energy to become a gas because of its molecular structure and the forces that hold its molecules together. Water molecules are made up of two hydrogen atoms bonded to one oxygen atom. These molecules are held together by strong hydrogen bonds, which require a significant amount of energy to break.

In order for water to become a gas, these hydrogen bonds need to be broken. This process, known as vaporization, requires a large amount of energy. The energy is used to overcome the intermolecular forces between water molecules, allowing them to break free and become a gas.

In comparison, oxygen molecules are smaller and have weaker intermolecular forces, making it easier for them to become a gas. This is why water requires more energy to become a gas than oxygen.

Additionally, the energy required for vaporization is also affected by the temperature and pressure of the surrounding environment. Higher temperatures and lower pressure make it easier for water to become a gas, as they provide the necessary energy to break the hydrogen bonds.

In summary, the structure and intermolecular forces of water molecules play a significant role in why it requires more energy to become a gas. The energy needed to break the hydrogen bonds is greater compared to other molecules, making the process of vaporization more difficult.