Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: DoctorBeaver on 28/11/2008 18:42:28

Title: What is a metal?
Post by: DoctorBeaver on 28/11/2008 18:42:28
I know elements like iron and aluminium are metals. But then there's stuff like calcium and sodium. They certainly don't look like what I would call metal.

So what exactly is a metal?
Title: What is a metal?
Post by: lightarrow on 28/11/2008 19:08:46
They certainly don't look like what I would call metal
Why?
Title: What is a metal?
Post by: DoctorBeaver on 28/11/2008 19:38:09
I wouldn't pick up a piece of sodium or calcium and think "Oooh, I could turn this on a lathe and make something nice".
Title: What is a metal?
Post by: Chemistry4me on 29/11/2008 05:08:01
It bonds ionically with non-metals, just an idea...
Title: What is a metal?
Post by: Chemistry4me on 29/11/2008 05:09:14
Metals are good conductors of heat and electricity...
Title: What is a metal?
Post by: lyner on 29/11/2008 11:00:56
Na and K are not as strong as many metals but they are shiny (because of their high conductivity) when freshly cut, malleable, ductile, good thermal conductors. What properties do they share with C,S,I?
Title: What is a metal?
Post by: lightarrow on 29/11/2008 12:52:11
I wouldn't pick up a piece of sodium or calcium and think "Oooh, I could turn this on a lathe and make something nice".
So you're not looking for a definition of "metal" but for a definition of "what is possible to turn on a lathe and making something nice".
A metal is a chemical element the structure of which is determined by the "metallic bond". It means that positive ions forms a lattice and the remaining electrons interact with all the first so that they can move freely through the entire lattice. According to this definition, Na and Ca are metals.
Title: What is a metal?
Post by: lyner on 29/11/2008 18:00:46
Most elements are metals and an even bigger proportion of solid elements are metals - it's only a way of categorising things because they share certain common properties - not the other way round.
Title: What is a metal?
Post by: Bored chemist on 29/11/2008 18:45:25
I wouldn't pick up a piece of sodium or calcium and think "Oooh, I could turn this on a lathe and make something nice".
So laburnum wood is a metal.
http://www.scottish-crafts.co.uk/pdfwoodturningpages/laburnum%20goblets.htm
Title: What is a metal?
Post by: lyner on 30/11/2008 00:32:35
How about a nice turned mercury candlestick?
OK in the deep freeze but the candle would melt it.