How Molecules Interact
H(2)Ow?
It's familiar as a solid, liquid and gas. Whatever form it takes, it's always H2O.
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Find out how molecules interact
The difference between the number of electrons and protons in an atom determines how strong the charge is, and what that atom can bond with. Atoms with a positive charge will be attracted to negatively charged atoms to form a molecule. This bonding between atoms is the key to how molecules interact with each other. The positioning of atoms in a molecule may give it polarity. If two positively charged atoms are near each other in a molecule, that area may carry a slighty positive charge, while elsewhere the charge may be slightly negative.
An example of this is water.
H2O is one of the most common molecules we encounter, and the position of the positively charged hydrogen atoms is critical in how it changes state, from solid (as ice) to liquid to gas (as steam).
Other molecules interact with water, combining with the atoms to create new soluble liquids. Fizzy drinks are carbonated, an example of a chemical reaction between carbon dioxide and water that only occurs under pressure.
Content last updated: 31/01/2002








