Extraction of metals

Extraction of metals

Lesson 2 - Chemical changes

Multiple Choice

What are the products formed when a group 1 metal reacts with water

• metal hydroxide and hydrogen

• metal oxide and hydrogen

• Water and a salt

• metal and water

Multiple Choice

What is formed when a group 2 metal reacts with water

• metal hydroxide + Hydrogen

• metal oxide and hydrogen

• water and a salt

• water and the metal

Multiple Choice

Metals become positive ions - true or false

• True

• False

Multiple Choice

True or false - as a metal atom gets larger it becomes more reactive

• True

• False

Multiple Choice

The reactivity series in metals is _______ to the reactivity series trend in halogens.

• the opposite

• the same

Multiple Choice

What can we do when balancing an equation

• Add large numbers (coefficients)

• Take away subscripts (small numbers)

• Change the elements

• rearrange the compounds

Multiple Choice

Prior knowledge - what is the most reactive metal out of these

• Copper

• Iron

• Sodium

• Gold

Multiple Choice

Prior knowledge - what is the correct order of reactivity for the metals below from most reactive (top) to least reactive (last)

• Sodium

  Magnesium

  Zinc

  Iron

  Copper

  Gold

• Iron

  Sodium

  Zinc

  Gold

  Magnesium

  Copper

• Zinc

  Gold

  Magnesium

  Sodium

  Copper

  Iron

Metals in the real world

Most metals are found on the earth as compounds which are called ores

An example is haematite - this contains iron

There can be many ores for each metal

Metals like gold, silver and platinum are very unreactive, these will be found in their native states (as elements).

What is an ore

An ore is a substance such as haematite (contains iron) which contains enough of a metal to make a profit from extraction.

I.e. It costs less to extract it that what you can sell it for.

Reduction vs oxidation

In these slides we have mentioned the metal is reduced, this means the carbon is oxidised.

You can think about it like this:

The carbon is oxidised (gains oxygen)

The metal is reduced (loses oxygen)

Multiple Choice

Un-reactive metals are found on earth as

• parts of a compound

• as elements in their native states

Multiple Choice

An ore is

• the pure metal i.e. gold found in the environment

• Something you use to row a boat

• a substance which contains enough of a metal to make a profit from extraction

Multiple Choice

Most metals are extracted by

• Heating with carbon and electrolysis

• smashing the ore down to powder and using water

• Most don't need to be extracted as they are already found as elements

Multiple Choice

A metal extracted by heating with carbon is

• Steel

• Iron

• Aluminium

• Silver

Multiple Choice

A metal extracted by using electrolysis is

• Zinc

• Copper

• Lead

• Aluminium

Multiple Choice

The correct word equation for the extraction of iron is....

• Iron + Carbon --> Iron + Oxygen

• Iron oxide --> Iron + Oxygen

• Iron oxide + Carbon --> Iron + Carbon dioxide

Multiple Choice

The correct word equation for the electrolysis of aluminium is

• Aluminium oxide --> aluminium + oxygen

• Aluminium oxide + carbon --> aluminium + oxygen

• Aluminium oxide + carbon --> aluminium + carbon dioxide

Task 2 - to complete on your docs

Using your knowledge of the reactivity series you are to predict are going to predict which of these metals you can extract by heating (reducing) with carbonand explain why.

Watch the following video for copper first and apply this to magnesium oxide and lead oxide 

https://www.youtube.com/watch?v=wNqiCjR2ics

Record any observations you would expect to make - in the table on the following slide - copper will be done for you

Example -

Copper oxide (II)

Copper would be reduced in this reaction because it is less reactive than carbon, observations I would see are small chunks and flakes of copper in the crucible after heating and the carbon would have escaped as carbon dioxide gas. The carbon will displace the less reactive copper from the oxygen to form carbon dioxide.

Multiple Choice

What is the correct word equation for the extraction of copper

• Copper + carbon --> copper oxide + carbon

• Copper oxide --> copper + oxygen

• Copper oxide + carbon --> copper + carbon dioxide

Multiple Choice

Why was magnesium not extracted from its ore when heated with carbon?

• There wasn't enough heat

• Magnesium is more reactive than carbon

Tungsten

Tungsten is another metal that is reduced from its ore, however hydrogen is used instead of carbon even though carbon would be cheaper.

This is because carbon forms a compound with the tungsten during this process (tungsten carbide), where as the hydrogen forms water with the oxygen and the tungsten extracted using hydrogen is very pure

The word equation is :

Tungsten oxide(s) + hydrogen(g) --> tungsten(s) + water (g)(as steam).

Multiple Choice

What are the correct products formed from the reaction we just saw

• Water(l) + Tungsten(s)

• carbon dioxide + tungsten

• Tungsten(s) + Water (g)

Multiple Choice

Can you choose the correct balanced symbol equation for

WO_3(s) + H_2(g) 🡪 W_(s) + H₂O_(g)

• WO_3(s) + 3H_2(g) 🡪 W_(s) + 3H₂O_(g)

• WO_3(s) + 4H_2(g) 🡪 W_(s) + 4H₂O_(g)

• It's already balanced

Plenary quiz - get ready

Multiple Select

Which metals here can be extracted from their ores by heating with carbon, choose all you think are right

• Iron

• Magnesium

• Sodium

• Copper

• Zinc