what is the definition of IMPURITY??

Question

i have a ceminar on that..
so in introduction i have to describe that..
pls tell me if u know?

Answer 1

Impurities are substances inside a confined amount of liquid, gas, or solid, which differ from the chemical composition of the material or compound.

Impurities are either naturally occurring or added during synthesis of a chemical or commercial product. During production, impurities may be purposely, accidentally, inevitably, or incidentally added into the substance.

The level of impurities in a material are generally defined in relative terms. Standards have been established by various organizations that attempt to define the permitted levels of various impurities in a manufactured product. Strictly speaking, then, a material's level of purity can only be stated as being more or less pure than some other material.
Impurities can be destructive when they obstruct the working nature of the material. Examples include ash and debris in metals and leaf pieces in blank white papers. The removal of impurities is usually done chemically. For example, in the manufacturing of iron, calcium carbonate is added to the blast furnace to remove silicon dioxide from the iron ore. Zone refining is an economically important method for the purification of semiconductors.

However, some kinds of impurities can be removed by physical means. A mixture of water and salt can be separated by distillation, with water as the distillate and salt as the solid residue. Impurities are usually only physically removed from liquids and gases. Removal of sand particles from metal ore powders is one example with solids.

No matter what method is used, it is usually impossible to separate an impurity completely from a material. What technicians can do is to increase the purity of a material to as near 100% as possible or economically feasible.
Impurities can, though, add constructive properties to a material. Alloys are metals with impurities. The resulting combination has desirable properties not found in the constituent materials. Steel, for example, is made by introducing a controlled amount (less than 2%) of carbon into pure iron. In the manufacturing of solar cells, pure silicon is mixed with a very small portion of impurities (0.001% to 0.01%) in the form of phosphorus and boron atoms in order to generate electricity. This is known as doping of silicon and is constructive, although the phosphorus and boron could be called impurities.

Answer 2

Definitions of impurity on the Web:

worthless or dangerous material that should be removed; "there were impurities in the water"
the condition of being impure
wordnet.princeton.edu/perl/webwn

Impurities (im- + pure + -ity + -s) refer to any substances inside a confined amount of liquid or gas, or a piece of solid, that it's chemical composition is different to the majority materials.
en.wikipedia.org/wiki/Impurity

something that, when mixed into something else, makes that mixture unclean or lowers the quality.
www.wef.org/publicinfo/newsroom/wastewater_glossary.jhtml

Any foreign or undesired material that gets incorporated into the semiconductor material or layers above the silicon surface.
www.st.com/stonline/press/news/glossary/i.htm

An element added to the semiconductor substrate material (either germanium, silicon, or gallium arsenide) in the fabrication process to create a P-type or N-type region. For germanium, the impurities are arsenic and bismuth. For silicon, the impurities are boron, phosphorus, and aluminum. and for gallium, arsenic and phosphorus.
www.nuhorizons.com/Glossary/DiscreteSemi.html

is a foreign particle in the stone such as sand spot or gypsum in opal. Jelly opal: is clear, almost colourless opal.
www.costellos.com.au/opals/glossary.html

Any undesirable extraneous material present in a fleece or textile product.
www.llamapaedia.com/wool/glossary.html

any foreign material incorporated into an Integrated Circuit structure. Impurities can be deliberately added Dopants or unwanted Contamination.
www.icknowledge.com/glossary/i.html

An element unintentionally allowed in a metal or alloy. Some impurities have little effect on properties; others will grossly damage the alloy.
www.tdcoating.com/td_glossary_terms4.htm

An element that is allowed into a metal or alloy. Impurities slightly change the properties of the material in some circumstances and can completely damage it in others.
www.ferralloy.com/casting-glossary.htm

a substance that causes another substance to be contaminated.
www.unco.edu/chemquest/b_gloss.htm

Any foreign object in the pool or spa water.
www.dadelandpool.com/vocab.html

An item present in a mineral which is not part of its integral structure, and may change its optical properties, such as color.
www.inlandlapidary.com/user_area/glossaryI.asp

Answer 3

im·pu·ri·ty (m-pyr-t) KEY

NOUN:
pl. im·pu·ri·ties
The quality or condition of being impure, especially:
Contamination or pollution.
Lack of consistency or homogeneity; adulteration.
A state of immorality; sin.
Something that renders something else impure; an inferior component



like for example a pure glass of water that could stand for anything pure then u add mud to it making it impure wich stands for anything bad

Answer 4

An impurity is any form of any matter that is found within some matter which is pure. (Pure meaning without change at the smallest, most whole level that still has all the properties of the substance at a macroscopic level).

Note the meaning of "pure" and take its opposite. An "impurity" would disrupt what it means to be pure.

Answer 5

Impurity is:

The quality or condition of being impure, especially:

1. Contamination or pollution.

2. Lack of consistency; adulteration.

3. A state of immorality; sin.

Answer 6

(m)

1 : something that is impure or makes something else impure

2 : the quality or state of being impure

Answer 7

hey..the answer is very simple...
Impurity is any undesirable and extraneous substance that causes another substance to be contaminated although the impurity could have a good / bad effect on the primary substance..

Answer 8

impurity is an entity impairing the concentration of a substance making it impure.

Answer 9

hey! i know-i know....research is what you were supposed to do instead of ask questions on the net