Chemistry & Environmental Dictionary

Mass - Mixture


The quantity of matter contained in a particle or body regardless of its location in the universe and the gravitational force applied to it. Mass is constant, while weight is affected by the distance of the object from the center of the earth (or other such body). Mass is not affected by gravity. The mass of an object is responsible for its inertia (i.e. its resistance to being accelerated).

Melting Point (freezing point)

The temperature at which the crystals of a pure substance are in equilibrium with the liquid phase at atmospheric pressure. This temperature is commonly referred to as melting point when a substance is approaching it from its solid state and is referred to as freezing point when a substance is approaching it from its liquid state.


A rare cancer known that affects thin membranes surrounding lungs and other internal organs. Mesothelioma has been associated with asbestos exposure. title="Asbestos: A Manufacturing Health Hazard Dating to Prehistoric Times">More information)


Elements that form cations when compounds of it are in solution and oxides of the elements form hydroxides rather than acids in water. Most metals are conductors of electricity, have crystalline solids with a metallic luster and have a high chemical reactivity. Many of these elements are hard and have high physical strength. The metal series includes all elements of the alkali, alkali-earth, inner-transition (lanthanides and actinides series), transactinides and transition series as well as some elements of the metalloid series (elements: Ge, Sb and Po).


this term is no longer commonly used by chemists, however, it refers to elements that exhibit some properties of metals and nonmetals. These elements tend to be semiconductors. Silicon is an extremely important example of these elements. Without the semiconductive properties silicon you would not be reading this text right now as most microchips and microprocessors are made with silicon and without these processors computers as we now know them would not exist.

Millibarns (mbarns)

A measurement of area equal to 1/1,000 of a barn or E -27 cm2.


an association of substances, which cannot be represented by a chemical formula. In a heterogeneous mixture the substances are not uniformly dispersed, as is the case in Italian salad dressing. In the purest sense, the term "homogeneous" refers to a chemical composition of only one compound or element, but the term "homogeneous mixture" is loosely used to describe two or more substances that are uniformly dispersed as in a solution of water and sodium chloride (table salt).

Dictionary Navigation

Citing this page

If you need to cite this page, you can copy this text: