Chemical Changes: Extracting Metals

Question 1

How are most metals found in the earth? Why is this?

Answer 1

• metals are using found as compounds
• lots of common metals react with oxygen to form their oxides
• this is because metals tend to be fairly reactive

Question 2

What is an ore?

Answer 2

A rock that contains enough metal within it to make extraction of the metal worthwhile.

Question 3

What is a native metal? How are these extracted?

Answer 3

A metal that is found naturally in the earth’s crust and is not bonded to any other element.
These can just be extracted by mining.

Question 4

What are some examples of native metals?

Answer 4

gold, silver

Question 5

How can metals less reactive than carbon be extracted?

Answer 5

By reduction with carbon. This where carbon is used to displace the metal and bond to oxygen in its place.

Question 6

What elements can be extracted by reduction with carbon?

Answer 6

zinc, iron, tin, lead, copper

Question 7

What elements are more reactive than carbon? What method do they have to be extracted with?

Answer 7

• potassium, sodium, calcium, magnesium, aluminium
• electrolysis

Question 8

Why can tungsten not be extracted using carbon? What is used instead?

Answer 8

• if carbon is used to extract tungsten from tungsten oxide then tungsten carbide is produced
• this is explosive
• hydrogen is used to reduce tungsten instead