Lesson 57 Extraction of Metals

1
Lesson 57 Extraction of Metals

• Could you gives the name of the ores from which
  aluminium, copper, iron and lead are extracted ?
  
• Is there any metal that exists in free state and
  need not be extracted from the ore ?
• How are mercury and silver extracted from their
  ores ?

2
Could you gives the name of the ores from which
aluminium, copper, iron and lead are extracted ?

• Aluminium ore
• Bauxite, mainly Al2O3
• Copper ore
• Copper pyrite, mainly CuFeS2
• Iron ore
• Haematite, mainly Fe2O3
• Lead ore
• Galena, mainly PbS
• Refer to pg 88-89 and 233

3
Is there any metal that exists in free state and
need not be extracted from the ore ?

• Yes, but very rare.
• Examples are gold Au and mercury Hg

4
How are mercury and silver extracted from their
ores ?

• Mercury (Hg) and Silver (Ag) can be extracted by
  heating the ores alone.
• Most Hg and Ag compounds are not stable to heat
  and decompose readily to give Hg and Ag metal.

5
Thermal decomposition of metal oxide
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Thermal decomposition of metal oxide

• Word equationmercury(II) oxide ?
• Unbalanced chemical equation
• Balanced chemical equation

7
Thermal decomposition of metal oxide

• Word equationmercury(II) oxide ? mercury
  oxygen
• Unbalanced chemical equation
• Balanced chemical equation

8
Thermal decomposition of metal oxide

• Word equationmercury(II) oxide ? mercury
  oxygen
• Unbalanced chemical equationHgO(s) ? Hg(l)
  O2(g)
• Balanced chemical equation

9
Thermal decomposition of metal oxide

• Word equationmercury(II) oxide ? mercury
  oxygen
• Unbalanced chemical equationHgO(s) ? Hg(l)
  O2(g)
• Balanced chemical equation2HgO(s) ? 2Hg(l)
  O2(g)

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Thermal decomposition of metal oxide
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Thermal decomposition of metal oxide

• Word equationsilver oxide ? silver oxygen
• Unbalanced chemical equationAg2O(s) ? Ag(s)
  O2(g)
• Balanced chemical equation2Ag2O(s) ? 4Ag(s)
  O2(g)

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Classwork

• pg248 Q6