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FROM GLASSES TO GASES:
The Science of Matter


a book in the eXperiment! series by David Darling



From Glasses to Gases book cover Contents
1. Matter of Interest
2. Solids and Solutions
3. Liquids and Skins
4. How Slow the Flow?
5. Str-e--t----c------h!
6. New Materials, New Properties
Glossary





Glossary



atom

There are 92 different kinds of atoms in nature. All substances are made of atoms or of combinations of atoms called molecules.


density

The amount of matter, or mass, in a unit volume. Density measures how concentrated a piece of matter is.


detergent

A cleaning substances. More detergents are continually being developed to remove grease and dirt more effectively.


elasticity

A measure of the springiness of a material. A substance with high elasticity can be stretched quite far and still return to its original shape.


insoluble

A substance is insoluble if it will not dissolve in a particular liquid. A substance may be soluble in one liquid but insoluble in another.


matter

Anything that takes up space. This includes all solids, liquids, and gases.


metal fatigue

The weakness that may develop in a piece of metal that undergoes repeated stretching or vibration. It begins when small cracks develop on the metal's surface.


molecule

The smallest part of a substance that still has the chemical properties of that substance. A molecule consists of atoms joined together.


plastic liquid

A liquid that will only flow when pushed or squeezed.


solubility

A measure of how well a substance dissolves in a particular liquid. The solubility may be different in one liquid (e.g., water) than in another (e.g., alcohol).


solution

A mixture of a liquid and one or more other substances. These other substances may be solids, liquids, or gases.


solvent

The liquid in which a substance is dissolved.


state

The condition of a piece of matter – whether it is a solid, a liquid, or a gas.


surface tension

The force acting across the surface of a liquid that makes the liquid seem to have an elastic skin. It is caused by unbalanced forces between molecules at the surface.


suspension

A liquid in which tiny solid particles hand without sinking to the bottom.


thixotrope

A liquid that thickens if left undisturbed but flows easily again if shaken or stirred.


viscoelastic

A liquid that is both sticky (viscous) and springy (elastic) is viscoelastic.


viscosity

A measure of how well a liquid or a gas flows. A substance with a low viscosity flows more easily than one with high viscosity.


viscous

A liquid or gas is called if viscous if it has a high viscosity. For example, syrup and tar are viscous.


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