title: extraction of metals and reduction date

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Enter the room in silence. Put your planner, pencil case, exercise book and any other equipment you will need on your desk. Place your bags in the cupboards.

Title: Extraction of metals and reduction Date:

identify substances reduced by loss of oxygen

explain how extraction methods depend on metal reactivityinterpret or evaluate information on specific metal extraction processes.

Extraction, oxidation, reduction

Prior knowledge:

Activate- Extraction of metals and reduction

• Q. Where do metals come from?

PlatinumGoldSilverCopperLeadTinIron

ZincAluminiumMagnesiumCalciumLithiumSodiumPotassium

• The elements lowest on the reactivity series (beneath copper) are found as elemental metals.

• This is because they have such low reactivity, that they have remained uncombinedsince they were first formed billions of years ago….

• The only extraction that is needed, is to dig them up through mining.

Platinum

Gold

Silver

Ore

“A rock containing enough ofa metal for it to be economical

to extract.”

• Mining

Metal compound

• Crush and powder Ore.• Remove waste rock.

Elemental Metal

• Chemical Processes

Extracting MetalsHowever, most metals are found inside compounds inside ores.

• Shaped

Extracting MetalsHowever, most metals are found inside compounds inside ores, and require chemical processes to extract them.

PotassiumPotassium chlorideSylvite Ore

• Crush and powder Ore.• Remove waste rock.

• Chemical processes

Haematite Ore Iron oxide Iron

• Crush and powder Ore.• Remove waste rock.

• Chemical processes

What are the chemical processes?https://www.youtube.com/watch?v=fxBIgbRT8fw

Reduction with carbon

Native elementsNo chemical processes needed

*

*

*Carbon and hydrogen* are not metals, but are often put on the reactivity series for comparison.

Activate- Chemical processes

Reduction with Carbon• Carbon will displace elements less reactive than it from their oxides.• The metal oxide is heated with carbon, and carbon dioxide + the pure metal are produced.

Reduction1. The removal of oxygen.

Example 1:Copper oxide + Carbon Carbon dioxide + Copper

2 CuO(s + C (s) CO2 (g) + 2 Cu(s)

Activate

Example 2:lead oxide + carbon carbon dioxide + lead

2 PbO(s) + C (s) CO2 (g) + 2 Pb(s)

Carbon is morereactive than lead

so is able to displace(reduce) it.

1. It’s had oxygen removed.

Activate- Reduction with Carbon

Example 3:tin oxide + carbon carbon dioxide + tin

SnO2(s) + C (s) CO2 (g) + Sn(s)

Carbon is morereactive than tin

so is able to displace(reduce) it.

1. It’s had oxygen removed.

Activate- Reduction with Carbon

Example 4:Iron (III) oxide + carbon carbon dioxide + iron

2 Fe2O3 (s) + 3 C (s) 3 CO2 (g) + 4 Fe(s)

Carbon is morereactive than tin

so is able to displace(reduce) it.

1. It’s had oxygen removed.

Activate- Reduction with Carbon

Self assessment & Corrections1. Metals can be found inside rocks called ______, which contain enough

metal for it to be ___________ to extract.

2. The metals that are found as native elements all have low ____________.They include ____________, _____________ and ______________.

3. Metals less reactive than carbon can be extracted using ______________.

4. Reduction involves heating the metal oxide in a ___________ with ____________. The __________ removes the oxygen and forms carbon_________. This ____________ the metal oxide, forming the pure ___________.

ores

economic

reactivity

silver gold platinum

reduction

furnacecarbon carbon dioxide

reduces metal

Keywords: Reduces, economic, ores Metal, Carbon, Carbon, Furnace, Dioxide, reduction, furnace

Demonstrate

Self assessment & Corrections

5. Complete the generic word equation for reduction:

Metal oxide + carbon _______________ + ____________

6. State the meanings of the word reduction:

• The removal of ____________.

carbon dioxide metal

oxygen

Demonstrate

7. Complete the reduction word equations.

Zinc oxide + __________ carbon dioxide + ____________

Iron oxide + carbon _______________ + ___________

_____________ + _____________ carbon dioxide + tin

lead oxide + _____________ ______________ + lead

________________ + carbon ____________ + copper

Self assessment & Corrections

carbon zinc

carbon dioxide iron

tin oxide carbon

carbon carbon dioxide

copper oxide carbon dioxide

Demonstrate

9. The reaction below does not occur, use the reactivity series to explain why.

Aluminium oxide + carbon carbon dioxide + Aluminium2 Al2O3 + 3 C 3 CO2 + 4 Al

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………..………………………………………………………………………………………………………………………..…

Self assessment & Corrections

• Carbon is less reactive than aluminium.• As it is lower on the reactivity series.• This means it cannot displace aluminium from its oxide.• So it cannot reduce it by removing the oxygen.

Demonstrate

Self assessment & Corrections

• Electrolysis

10. Name the method used the extract metals that are more reactive than carbon.

…………………………………………………………………………………………………………………………

We will study this in a few lessons time!

Demonstrate

Electrolysis

Reduction with carbon

Summary of extraction techniques

Native Metals

“Aluminium, magnesium, calcium, sodium andpotassium are more reactive than carbon, socannot be extracted by reduction (displacement).Instead we use a process called electrolysis”