Scientists Say: Surface tension
Surface tension (noun, “SUR-face TEN-shun”)
This is an effect seen when liquid meets air. The molecules in the liquid are more attracted to each other than they are to the nearby air. This makes them clump together at the liquid’s surface. Surface tension is what makes the surface of a very full glass of water look like it is covered with an invisible membrane. It’s also why some small insects can walk on top of the water — surface tension is just strong enough to hold them up.
In a sentence
Soap can disrupt surface tension by making it harder for the water molecules to bunch together.
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(for more about Power Words, click here)
disrupt (n. disruption) To break apart something; interrupt the normal operation of something; or to throw the normal organization (or order) of something into disorder.
force Some outside influence that can change the motion of a body, hold bodies close to one another, or produce motion or stress in a stationary body.
liquid A material that flows freely but keeps a constant volume, like water or oil.
membrane A barrier which blocks the passage (or flow through of) some materials depending on their size or other features. Membranes are an integral part of filtration systems. Many serve that same function as the outer covering of cells or organs of a body.
molecule An electrically neutral group of atoms that represents the smallest possible amount of a chemical compound. Molecules can be made of single types of atoms or of different types. For example, the oxygen in the air is made of two oxygen atoms (O2), but water is made of two hydrogen atoms and one oxygen atom (H2O).
surface tension The surface film of a liquid caused by the strong bonds between the molecules in the surface layer.