a chemically inactive element, compound or material. Because of their extremely low chemical activity the noble gasses are considered to be inert substances. This term is also used for subst
A substance or material that contains only one kind of compound or one element. Homogeneous is Latin for "the same kind". An example of a homogeneous substance would be pure water,
A mixture or material consisting of more than one substance. The earth's atmosphere is heterogeneous in that it typically consists of 20.7% oxygen, 78% nitrogen, 0.93% argon and 0.03% CO2 wi
The heat required to convert a substance from the liquid to the gaseous state with no temperature change. This is also called the latent heat of vaporization.
Any material or substance, which even in normal use, poses a risk to health, safety, property or the environment. Hazardous materials are broken down into nine primary classes by the United
The vertical columns (major classes or divisions) into which elements are arranged in the periodic table of elements. There are three common numbering systems for these groups:
The temperature scale where 32 degrees is the freezing point of water and 212 degrees at 760mm Hg (sea level) is the boiling point of water. To convert from Fahrenheit to centigrade, subtrac
The sudden and violent release of mechanical, chemical or nuclear energy from a confined space which creates a heat wave that travels at subsonic speeds. Often used interchangeably with deto
Created in 1970 as an agency of the United States federal government, charged with protecting the environment and enforcing environmental laws and regulations. The EPA did not play a signifi