Words to Know

WORDS TO KNOW

A

Abrasive
a powdery material used to grind or polish other materials
Absolute zero
the lowest temperature possible, about –273°C (–459°F)
Actinide family
elements in the periodic table with atomic numbers 90 through 103
Alchemy
a kind of pre-sceince that existed from about 500 B.C. to about the end of the 16th century
Alkali metal
an element in Group 1 (IA) of the periodic table
Alkali
a chemical with properties opposite those of an acid
Alkaline earth metal
an element found in Group 2 (IIA) of the periodic table
Allotopes
forms of an element with different physical and chemical properties
Alloy
a mixture of two or more metals that has properties different from those of the individual metals
Alpha particles
tiny, atom-sized particles that can destroy cells
Alpha radiation
a form of radiation that consists of very fast moving alpha particles and helium atoms without their electrons
Amalgam
a combination of mercury and at least one other metal
Amorphous
without crystalline shape
Anhydrous ammonia
dry ammonia gas
Antiseptic
a chemical that stops the growth of germs
Aqua regia
a mixture of hydrochloric and nitric acids that often reacts with materials that do not react with either acid separately

B

Battery
a device for changing chemical energy into electrical energy
Biochemistry
the field of chemistry concerned with the study of compounds found in living organisms
Biocompatible
not causing a reaction when placed into the body
Bipolar disorder
a condition in which a person experiences wild mood swings
Brass
an alloy of copper and zinc
Bronze Age
a period in human history ranging from about 3500 B.C. to 1000 B.C., when bronze was widely used for weapons, utensils, and ornamental objects
Bronze
an alloy of copper and tin
Buckminsterfullerene
full name for buckyball or fullerene; see Buckyball
Buckyball
an allotrope of carbon whose 60 carbon atoms are arranged in a sphere-like form

C

Capacitor
an electrical device, somewhat like a battery, that collects and then stores up electrical charges
Carat
a unit of weight for gold and other precious metals, equal to one fifth of a gram, or 200 milligrams
Carbon arc lamp
a lamp for producing very bright white light
Carbon-14 dating
a technique that allows archaeologists to estimate the age of once-living materials by using the knowledge that carbon-14 is found in all living carbon materials; once an organism dies, no more carbon-14 remains
Cassiterite
an ore of tin containing tin oxide, the major commercial source of tin metal
Catalyst
a substance used to speed up or slow down a chemical reaction without undergoing any change itself
Chalcogens
elements in Group 16 (VIA) of the periodic table
Chemical reagent
a substance, such as an acid or an alkali, used to study other substances
Chlorofluorocarbons (CFCs)
a family of chemical compounds consisting of carbon, fluorine, and chlorine that were once used widely as propellants in commercial sprays but regulated in the United States since 1987 because of their harmful environmental effects
Corrosive agent
a material that tends to vigorously react or eat away at something
Cyclotron
a particle accelerator, or "atom smasher," in which small particles, such as protons, are made to travel very fast and then collide with atoms, causing the atoms to break apart

D

Density
the mass of a substance per unit volume
Diagnosis
finding out what medical problems a person may have
Distillation
a process by which two or more liquids can be separated from each other by heating them to their boiling points
"Doped"
containing a small amount of a material as an impurity
Ductile
capable of being drawn into thin wires

E

Earth
in mineralogy, a naturally occurring form of an element, often an oxide of the element
Electrolysis
a process by which a compound is broken down by passing an electric current through it
Electroplating
the process by which a thin layer of one metal is laid down on top of a second metal
Enzyme
a substance that stimulates certain chemical reactions in the body

F

Fabrication
shaping, molding, bending, cutting, and working with a metal
Fission
the process by which large atoms break apart, releasing large amounts of energy, smaller atoms, and neutrons in the process
Fly ash
the powdery material produced during the production of iron or some other metal
Frasch method
a method for removing sulfur from underground mines by pumping hot air and water down a set of pipes
Fuel cell
any system that uses chemical reactions to produce electricity
Fullerene
alternative name for buckyball; see Buckyball

G

Galvanizing
the process of laying down a thin layer of zinc on the surface of a second metal
Gamma rays
a form of radiation similar to X rays

H

Half life
the time it takes for half of a sample of a radioactive element to break down
Halogen
one of the elements in Group 17 (VIIA) of the periodic table
Heat exchange medium
a material that picks up heat in one place and carries it to another place
Hydrocarbons
compounds made of carbon and hydrogen
Hypoallergenic
not causing an allergic reaction

I

Inactive
does not react with any other element
Inert gases
see Noble gases
Inert
not very active
Isotope
two or more forms of an element that differ from each other according to their mass number

L

Lanthanide family
the elements in the periodic table with atomic numbers 58 through 71
Laser
a device for making very intense light of one very specific color that is intensified many times over
Liquid air
air that has been cooled to a very low temperature
Luminescence
the property of giving off light without giving off heat

M

Machining
the bending, cutting, and shaping of a metal by mechanical means
"Magic number"
the number of protons and/or neutrns in an atom that tend to make the atom stable (not radioactive)
Magnetic field
the space around an electric current or a magnet in which a magnetic force can be observed
Malleable
capable of being hammered into thin sheets
Metals
elements that have a shiny surface, are good conductors of heat and electricity, and can be melted, hammered into thin sheets, and drawn into thin wires
Metalloid
an element that has characteristics of both metals and non-metals
Metallurgy
the art and science of working with metals
Micronutrient
a substance needed in very small amounts to maintain good health
Misch metal
a metal that contains different rare earth elements and has the unusual property of giving off a spark when struck
Mohs scale
a way of expressing the hardness of a material
Mordant
a material that helps a dye stick to cloth

N

Nanotubes
long, thin, and extremely tiny tubes
Native
not combined with any other element
Neutro radiography
a technique that uses neutrons to study the internal composition of material
Nickel allergy
a health condition caused by exposure to nickel metal
Nitrogen fixation
the process of converting nitrogen as an element to a compound that contains nitrogen
Noble gases
elements in Group 18 (VIIIA) of the periodic table
Noble metals
see Platinum family
Non-metals
elements that do not have the properties of metals
Nuclear fission
a process in which neutrons collide with the nucleus of a plutonium or uranium atom, causing it to split apart with the release of very large amounts of energy
Nuclear reactor
a device in which nuclear reactions occur

O

Optical fiber
a thin strand of glass through which light passes; the light carries a message through a telephone wire
Ore
a mineral compound that is mined for one of the elements it contains, usually a metal element
Organic chemistry
the study of the carbon compounds
Oxidizing agent
a chemical substance that gives up or takes on electrons from another substance
Ozone
a form of oxygen that filters out harmful radiation from the sun

P

Particle accelerator ("atom smasher")
a device used to cause small particles, such as protons, to move at very high speeds
Periodic law
a way of organizing the chemical elements to show how they are related to each other
Periodic table
a chart that shows how chemical elements are related to each other
Phosphor
a material that gives off light when struck by electrons
Photosynthesis
the process by which plants convert carbon dioxide and water to carbohydrates (starches and sugars)
Platinum family
a group of elements that occur close to platinum in the periodic table and with platinum in the Earth's surface
Polymerization
the process by which many thousands of individual tetrafluoroethlylene (TFE) molecules join together to make one very large molecule
Potash
a potassium compound that forms when wood burns
Precious metal
a metal that is rare, desirable, and, therefore, expensive
Proteins
compounds that are vital to the building and growth of cells
Pyrophoric
gives off sparks when scatched

Q

Quarry
a large hole in the ground from which useful minerals are taken

R

Radiation
energy transmitted in the form of electromagnetic waves or subatomic particles
Radioactive isotope
an isotope that breaks apart and gives off some form of radiation
Radiactive tracer
an isotope whose movement in the body can be followed because of the radiation it gives off
Radioactivity
the process by which an isotope element breaks down and gives off some form of radiation
Rare earth elements
see Lanthanide family
Reactive
combines with other substances relatively easily
Refractory
a material that can withstand very high temperatures and reflects heat back away from itself
Rodenticide
a poison used to kill rats and mice
Rusting
a process by which a metal combines with oxygen

S

Salt dome
a large mass of salt found underground
Semiconductor
a material that conducts an electric current, but not nearly as well as metals
Silver plating
a process by which a very thin layer of silver metal is laid down on top of another metal
Slag
a mixture of materials that separates from a metal during its purification and floats on top of the molten metal
Slurry
a soup-like mixture of crushed ore and water
Solder
an alloy that can be melted and then used to join two metals to each other
Spectra
the lines produced when chemical elements are heated
Spectroscope
A device for analyzing the light produced when an element is heated
Spectroscopy
the process of analyzing light produced when an element is heated
Spectrum
(plural: spectra) the pattern of light given off by a glowing object, such as a star
Stable
not likely to react with other materials
Sublimation
the process by which a solid changes directly to a gas when heated, without first changing to a liquid
Superalloy
an alloy made of iron, cobalt, or nickel that has special properties, such as the ability to withstand high temperatures and attack by oxygen
Superconductivity
the tendency of an electric current to flow through a material without resistance
Superconductor
a material that has no resistance to the flow of electricity; once an electrical current begins flowing in the material, it continues to flow foreover
Superheated water
water that is hotter than its boiling point, but which has not started to boil
Surface tension
a property of liquids that makes them act like they are covered with a skin

T

Tarnishing
oxidizing; reacting with oxygen in the air
Tensile
capable of being stretched without breaking
Thermocouple
a device for measuring very high temperatures
Tin cry
a screeching-like sound made when tin metal is bent
Tin disease
a change that takes place in materials containing tin when the material is cooled to temperatures below 13°C for long periods of time, when solid tin turns to a crumbly powder
Tincture
a solution made by dissolving a substance in alcohol
Template
a type of metal consisting of thin protective coating of tin deposited on the outer surface of some other metal
Toxic
poisonous
Trace element
an element that is needed in very small amounts for the proper growth of a plant or animal
Tracer
a radioactive isotope whose presence in a system can easily be detected
Transfermium element
any element with an atomic number greater than 100
Transistor
a device used to control the flow of electricity in a circuit
Transiiton metal
an element in Groups 3 through 12 of the periodic table
Transuranium element
an element with an atomic number greater than 92

U

Ultraviolet (UV) radiation
electromagnetic radiation (energy) of a wavelength just shorter than the violet (shortest wavelength) end of the visible light spectrum and thus with higher energy than visible light

V

Vulcanizing
the process by which soft rubber is converted to a harder, long-lasting product

W

Workability
the ability to work with a metal to get it into a desired shape or thickness