METALS

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METALS
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Subject Contents

1. Properties of metals
2. Reactivity series
3. Extraction of metals
4. Iron
5. Aluminium

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• Why are metals used in certain materials?
• What physical properties do the metals have?

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1. Physical Properties

• strong and tough
• used to make machines which can withstand stress
• ductile (can be drawn into wires) malleable
  (can be shaped into sheets)
• made into drink cans, foils etc

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• Good conductor of ________
• made into wires cables.
• ________ boiling melting points
• metal such as tungsten is used for manufacturing
  of lamp filaments.

electricity
High
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• Pure metals are ______.
• The atoms are of the same size therefore it is
  easier for layers of atoms to __________ each
  other.

soft
slide over
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Alloy

• In an alloy, the bigger atoms are added. Hence,
  the atoms of different sizes cannot slide over
  each other.
• Hence, the alloy is harder and stronger than pure
  metals.

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Alloy Elements present
Stainless Steel 73 iron, 18 chromium, 8 nickel , 1 carbon
Bronze 90 copper 10 tin
Brass 70 Copper 30 zinc
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QUICK RECAP
1) Stainless steel is an alloy. Which
elements does it contain? 2) Why is stainless
steel stronger than iron?

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• The Reactivity Series
• (A list of metals placed in order of reactivity)

Prepared by, Miss Wong
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The Reactivity Series

• is a list of some metals with the most reactive
  metals at the top and the least reactive metal at
  the bottom
• the series is worked out based on the reaction of
  
• ( i) metal with cold water/ steam
• (ii) metal with acid

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Please
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Ladies
Calling
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Sexy
Girl
K Potassium
Na Sodium
Ca Calcium
Mg Magnesium
Al Aluminium
Zn Zinc
Fe Iron
Sn Tin
Pb Lead
Cu Copper
Hg Mercury
Ag silver
Au Gold
Reactivity decreases
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I. Reaction of metal with water
metal water ? metal hydroxide hydrogen
Potassium with water
Sodium with water

• Lots of bubbles with flashes of light
• Explodes with cold water.

• Lots of bubbles
• Reacts very quickly

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• Reaction of metal with water

Calcium with water
Magnesium with water

• Very few bubbles
• Slow reaction

• Lots of bubbles
• Reacts readily

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• I. Reaction of metals with Cold Water

Potassium Explodes ?potassium hydroxide hydrogen
Sodium Reacts violently
Calcium Reacts readily
Magnesium Reacts very slowly
Aluminium No reaction
Zinc
Iron DO NOT react with cold water
Tin
Lead
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Reaction of Metals with Steam

• Some metals do not react with cold water but they
  do react with steam. Hence, the less reactive
  metals will react with steam.
• The metal is strongly heated until very hot.
• Glass wool is then heated to generate steam over
  the hot metal.

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II. Reaction of metals with steam
Magnesium Hot magnesium reacts violently with hot steam to form white powder (magnesium oxide) and hydrogen. Equation_______________________
Aluminium No reaction.
Zinc Hot zinc reacts readily with steam
Iron Hot iron reacts slowly with steam
Tin
Lead
Copper NO reaction with STEAM.
Mercury
Silver
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Question 1 Based on their reaction with water,
deduce the order of the reactivity of these 3
metals.
METAL Reaction with water
Calcium Slow
Magnesium Very slow
Potassium Fast

• Most reactive ---------------------------?
  Least reactive
• Potassium Calcium Magnesium

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• Reaction of metal with acid
• Example Mg 2HCl ? MgCl2 H2
• Sometimes, hydrogen is placed in the reactivity
  series. (below lead)
• Metals below hydrogen do not react with acids.
• (E.g copper, silver, mercury and gold do not
  react with acid.)

metal acid ? salt hydrogen
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• II .Reaction of metal with acid

Magnesium with acid
Zinc with acid

• some bubbles formed
• slow reaction

• Lots of bubbles formed
• moderately fast reaction

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• II. Reaction of Metals with Acid (HCl)

Potassium Explosive reaction ? Potassium chloride hydrogen
Sodium Explosive reaction
Calcium Reacts vigorously, lots of bubbles
Magnesium Reacts very fast
Zinc Reacts moderately fast
Iron Reacts slowly
Lead Very slow reaction
Copper No reaction
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• Order of reactivity

METAL Reaction with cold water/Steam Reaction with dilute HCl
Potassium React with cold water Explosive reaction
sodium React with cold water Explosive reaction
Calcium React with cold water Violent reaction
magnesium React with steam Moderately fast
Zinc React with steam Moderately fast
Iron React with steam Slow
Lead No reaction with water or steam No reaction
Copper No reaction with water or steam No reaction
Silver No reaction with water or steam No reaction
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1. What metal does not react with HCl?

• a. Calcium b. Copper c. Magnesium d.
  Zinc
• a. Lead b. Iron c. Zinc d. Copper

2. Which of the following metals does not produce
hydrogen when added to acid?
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3. a) Arrange the metals below in order of
reactivity, starting with the most reactive first.

• copper, iron, calcium, lead, sodium, zinc

b) From the list, name two metals that will not
react with cold water but will react with steam
and to give hydrogen.
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Displacement Reactions

• A more reactive metal will displace a less
  reactive metal from a solution of its salts.
• i) CuSO4 Zn ?
• ii) CuSO4 Fe ?

Cu ZnSO4
Cu FeSO4
iii) Cu ZnSO4 ? iv) Mg ZnSO4 ?
No Reaction!!!
Zn MgSO4
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Websites

• http//lgfl.skoool.co.uk/viewdetails_KS3.aspx?ID5
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