Metals are everywhere, from the mouth of a pimpled faced teenager to the track for a train to chug along on. Metals are an everyday encounter, but what is a metal? What kinds of metals are there?
There are many different angles and ways to evaluate metals. A metal, physically, is a substance that has high electrical and thermal conductivity. Metals have varying degrees of hardness (resistance of metal to “plastic deformation”), density (measure of the qualitative “heaviness” of a substance), malleability (deformed by compression without cracking or rupturing) and ductility (allows it to be reduced in a cross sectional area).
Metal has a definite melting point, meaning there is a point that metals always melt and that point doesn’t change. Metals can then often fuse with other metals to form “alloys”. With the exception of mercury (a constant liquid metal), metals are solids at ordinary temperature. Without this ability our spoons would melt before anyone could get a bit of their cereal.
Some metals are found in the pure state (kind of like saying these metals are virgins or they’ve never or aren’t mixed with other substances), but most of them are found in combination with other elements. These metals expand and thrive in the form of carbonates, oxides, and silicates, usually mixed with rock and “earthy materials” (dirt and/or sticks). Some of the metals commonly found combined with other elements and “earthy materials”, are lead, zinc, iron, copper, chromium, nickel, and mercury (you know, the liquid metal).
Much too soft to be of much value, virgin (or pure) iron is used continually as steel, which is, matter of fact, a compound. There are a select few metals which, in tiny amounts, are necessary to animal life and survival. Among these are iron, potassium, calcium, magnesium, and sodium. The body (including the human body)uses minute quantities of copper, aluminum, and manganese to fully function correctly.
Some metals are so rare that tons of ore (a source from which valuable matter is extracted) must be treated to get even a small amount of the pure metal. Radium is one of these. Recovering much needed metals from their ores is the science most commonly referred to as “metallurgy”, a mix between the words metal and surgery. Some scientists can have fun!
Many metals, when they are in the virgin state (or more commonly referred to as the “pure state”), have properties that are not truly wanted or needed. Because of this fact most of the metals that are constantly used today are either alloys or compounds.
Examples (alloys):
Table silver
Gold coins
Aluminum pans
