metals and alloys Flashcards
what is copper?
a metallic element
what are ores
compounds
how do you extract copper?
convert the ore to copper oxide
how do you remove oxygen form coper oxide?
heated with carbon
what is removal of oxygen called?
reduction
how do we purify copper?
through electryolosis
why is recycling cheaper than extracting copper from its ore?
it saves resources- dont need so many copper mines
it saves energy needed to crush rocks and to operate smelters and electrolysis cells
what is the anode?
impure copper
what does the anode do?
dissolves into the electrolyte and pure copper coats the cathode. The cathode is plated with new copper
explain copper?
low melting point. it is easy to melt and recycle, which makes it cheap
what is bad about recycling copper?
getting people to do it in the first place
sorting copper form other metals
what can contaminated copper be used to make?
alloys such as brass or bronze or electrolysed
what is electrolysis?
the break up of a chemical compound when you use an electric current
how do we purify copper?
use an electrolyte of copper ii sulphate solution
what is the pure and impure copper?
impure is anode
pure is cathode
why does the cathode gain mass?
because copper is plated on it
what is a gain in electrons called?
reduction
what deposits onto the cathode?
ions from the copper sulphate electrolyte gain electron and deposit
what happens at the anode?
it dissolves. Copper atoms in the anode turn into ions putting copper ions back into the electrolyte
what is loss of electrons called?
reduction
where do the impurities go?
to the bottom of the cell
what are the 2 equations for the anode and cathode?
anode- cu - 2e- —– cu2+
cathode- cu2+ + 2e- — cu
what is an alloy?
a mixture of a metal element with another element
what are the 4 alloys and give an example of what their made from?
brass contains copper and zinc
solder lead and tin
steel iron
amalgam mercury
explain steel?
much stronger than iron and does not rust (stainless steel)
what is an alloy called that can bend?
a smart alloy
what are shape memory alloys called?
alloys that can change shape at set temperatures
how do smart alloys help people with the risk of heart attacks?
they can be put into a persons artery, warmed up to change into a tube that holds the artery open
