CHEMISTRY 2ND EXAM

• Actinides- any of the series of fifteen metallic elements from actinium (atomic number 89) to lawrencium (atomic number 103) in the periodic table. They are all radioactive, the heavier members being extremely unstable and not of natural occurrence.
• Alkali metals- the metals in Group 1 of the periodic table of elements
• Alkaline earth metals- metals which belong to group 2 in the periodic table
• Alloy- a mixture of a metal with at least one other element, usually another metal
• Amalgma- an alloy of mercury and silver or tin. It is used for dental fillings because it can be shaped when warm and resists corrosion.
• Brass- an alloy of copper and zinc; does not tarnish and is used for doorknobs, buttons and musical instruments
• Corrosion- a natural process that converts a refined metal into a more chemically stable form such as oxide, hydroxide, or sulfide. It is the gradual destruction of materials by chemical and/or electrochemical reactions with their environment.
• Ductility is a measure of a material's ability to undergo significant plastic deformation before rupture, which may be expressed as percent elongation or percent area reduction from a tensile test.
• Electricalconductivity the degree to which a specified material conducts electricity.
• Lanthanides are a group of 15 chemical elements, with atomic numbers 57 through 71. All of these elements have one valence electron in the 5d shell.
• Luster is a gentle sheen or soft glow, especially that of a partly reflective surface.
• Malleability is a physical property of metals that defines the ability to behammered, pressed or rolled into thin sheets without breaking
• Ore a naturally occurring solid material from which a metal or valuable mineral can be profitably extracted.
• Reactivity the ease and speed with which an element combines, or reacts, withother elements and compounds
• Rusting the specific name given to the corrosion of iron; a chemical reaction between iron, oxygen and water.
• Solder an alloy of zinc and lead; is used in electronics to attach componentsto circuit boards
• Sonority is a nonbinary phonological feature categorizing sounds into a relativescale
• Steel an alloy containing iron and other elements
• Thermal conductivity is the rate at which heat passes through a specified material, expressed as the amount of heat that flows per unit time through a unit area with a temperature gradient of one degree per unit distance.
• Transition metals the elements in Groups 3 through 12 in the periodic table
• A metal is a material that, when freshly prepared, polished, or fractured, showsa lustrous appearance, and conducts electricity and heat relatively well. Metals aretypically malleable (they can be hammered into thin sheets) or ductile (can be drawninto wires).
• A ductile material is one that can be pulled out, or drawn into a long wire
• Conductivity is the ability of an object to transfer heat or electricity to another object
• The ease and speed with which an element combines, or reacts, with otherelements and compounds is called its reactivity.
• The chemical name for rust is hydrated iron oxide.
• Metalloids they often create amphoteric oxides and behave in the same manner as semiconductors. The usually considered elements on this group are boron, silicon, germanium, arsenic, antimony & tellurium.
• Bronze, an alloy of copper and tin, was commonly used by civilizations before iron extraction methods were developed
• Steel is an alloy of iron and other elements, including carbon, nickel and chromium.
• low carbon steel contains less than 0.25% carbon, high carbon steel contains more than 0.5% carbon.
• stainless steel – an alloy of iron that contains at least 11% chromium and smaller amounts of nickel and carbon, titanium steel – an alloy of iron and titanium.
• Shape memory alloy is a type of smart material made from metals that returns to its original shape after being deformed
• Nitinol is atype of shape memory alloy made from nickel and titanium.
• Copolymers molecules which are built up of at least two different kinds of monomer
• Crosslinking process of forming covalent bonds or relatively short sequences of chemical bonds to join two polymer chains together.
• Elastomer a natural or synthetic polymer having elastic properties, e.g. rubber
• Homopolymers polymers consisting of monomer of identical chemical structure
• Kevlar is a heat-resistant and strong synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, this high-strength material was used first commercially in the early 1970s as a replacement for steel in racing tires
• Monomer is a molecule that can be bonded to other identical molecules to form a polymer.
• Polymer a large molecule which is formed by repeated linking of small molecules called "monomers"

  a polymer is a molecular compound distinguishedby a very high molar mass, ranging into thousands and millions of grams, and is made
• Polymerization the process by which simple (monomer) molecules join together to form very large (polymer) molecules.