Fact of the Day: 15/10/2021
You may have heard the term “polar” used to describe water molecules in a chemistry or general science class. But what exactly does it mean when someone says that water is a “polar” molecule?
Britannica defines polarity as “the distribution of electrical charge over the atoms joined by the bond.” Even though the entire molecule may be electrically neutral, the atoms (of different elements) in the molecule may have slightly more positive or more negative charges distributed over to their side, resulting in the creation of partial charges.
In the case of water, the oxygen atom has a partial negative charge, while the hydrogen atoms each have a partial positive charge. This is due to the positioning of electrons. While the oxygen and hydrogen atoms are covalently bonded (that is, they share bonding electrons), electrons tend to stay closer to the oxygen atom than the hydrogen atoms because of the difference in electronegativity between oxygen and hydrogen. Overall, the charges cancel out, but the molecule is still polar because of the uneven distribution of charges within the molecule.
Reference(s) & Further Exploration:
- https://www.britannica.com/science/polarity-chemistry
- If you’d like to learn more about electronegativity, check out this article: https://www.britannica.com/science/electronegativity
Fact Author: Ace
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