Download - 13 Metals(2)
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Reactivity Series of Metals
Reactions of Metals
Effect of Heat on Metal Carbonates
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Reactivity Series of Metals
Chemical Properties of Metals
Metal reaction with cold water & steam
Metal reaction with hydrochloric acid
Reaction of Metals: Displacement Reactions
With aqueous ions of another metal
With the oxide of another metal
Reaction of Metal Oxides With carbon
With hydrogen
Effect of Heat on Metal Carbonates
Thermal stability & reactivity
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Recap:
Chemical Properties of Metals
Reaction with Water (Cold Water)
Metal + Cold WaterMetal Hydroxide + Hydrogen Gas
Eg. 2Na(s) + 2H2O(l)2NaOH(aq) + H2(g)
Which are some metals that react with cold water?
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Recap:
Chemical Properties of Metals
Reaction with Water (Steam)
Metal + SteamMetal Oxide + Hydrogen GasEg. Mg(s) + H2O(g)MgO(s) + H2(g)
Which metals only react with steam?
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Recap:
Chemical Properties of Metals
Reaction with Hydrochloric Acid
Metal + Hydrochloric AcidSalt + Hydrogen Gas
Eg. 2K(s) + 2HCl(l)
2KCl(aq) + H2(g)
The more vigorous the reactionThe higher it is in the reactivity series
The more reactive is the metal
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Reaction of Metals
With the Aqueous Ions of Another Metal
Displacement of metalsfrom solution
More reactive metals can displace less reactive
metals from their salt solutions.
This can be used to find the position of metals in
the reactivity series.
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Iron Nail in Copper(II) Sulphate Solution
Observations:
1. Reddish-brown solid forms on the surface of the
iron nail
2. Blue solution becomes pale green
Fe (s) + CuSO4 (aq) FeSO4 (aq) + Cu (s)Iron Copper(II) Sulphate
Solution
Iron(II) Sulphate
Solution
Copper
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Iron Nail in Copper(II) Sulphate Solution
Brown solid: Copper metal
Solution turns pale green
Copper has been removed from the solution.
Iron(II) sulphate solution is pale green in colour.
We say that
Iron has displacedcopper from thecopper(II) sulphate solution.
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Think!
What will happen when
a piece of magnesium strip is immersed in
a solution of copper(II) sulphate?
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Some Possible Observations
Deposit of the more reactive metal (from its
aqueous solution)
Colour of the solution may change
Heat may be given off
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Displacement Reactions are Redox Reactions
The more reactive metal is oxidized
The less reactive metal is reduced
For example,
Chemical Equation:
Fe (s) + CuSO4 (aq) FeSO4 (aq) + Cu (s)
Ionic Equation:
Fe (s) + Cu2+(aq) Fe2+ (aq) + Cu (s)
REDOX
reaction!
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Displacement Reactions are Redox Reactions
A more reactive metal:
readily gives up electrons in reactions
has greater tendency to form positive ions
As a result
A more reactive metal can displace
a less reactive metal,from its solution or metallic oxide.
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Reaction of Metals
With the Oxide of Another Metal
Displacement of metalsfrom metallic oxides
A more reactive metal can reduce the oxide of a less
reactive metal.
For example: Thermit reaction
2Al (s) + Fe2O3 (s) Al2O3 (s) + 2Fe(l)
http://www.youtube.com/watch?v=eBqh8iV6PtIhttp://www.youtube.com/watch?v=eBqh8iV6PtIhttp://www.youtube.com/watch?v=eBqh8iV6PtI -
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Reaction of Metals
With the Oxide of Another Metal
Thermit Reaction
2Al (s) + Fe2O3 (s) Al2O3 (s) + 2Fe (l)
The more reactive the metal is, the more readily it
forms compounds.
Unreactive metals tend to stay umcombined.
Iron(III) ion s are reduced to become iron atom s
Alum inium atoms are oxid ized to becom e alum inium (III) ions
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Carbon can remove oxygen from the oxides ofmetals that are not too high up in the Reactivity
Series.
The lower the position of a metal in theReactivity Series, the easier it is for carbon to
remove oxygen from the metal oxide.
Reaction of Metal Oxides With Carbon
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Reaction of Metal Oxides With Carbon
metal oxide reactionpotassium oxide
sodium oxide
calcium oxide
magnesium oxide
oxides are not reduced by carbon
zinc oxide
iron(II) oxide
lead(II) oxide
copper(II) oxide
oxides are reduced by carbon
silver oxide oxide is reduced by heating
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metals need to be extracted from their ores before
we can use them
metals below magnesium are often extracted fromtheir ores by reduction with carbon (WHY?)
metals above zinc cannot be extracted by reduction
with carbon bc they are stable (THEN WHAT?)
The Importance!
Reaction of Metal Oxides With Carbon
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Hydrogen can remove oxygen from metallic oxides,
producing the metal and water(steam).
metal oxide + hydrogenmetal + steam
The lower the position of a metal in the
Reactivity Series, the easier it is for hydrogen
to remove oxygen from the metal oxide.
Reaction of Metal Oxides With Hydrogen
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Reaction of Metal Oxides With Hydrogen
metal oxide reaction with hydrogenpotassium oxide
sodium oxide
calcium oxide
magnesium oxidezinc oxide
heated metal oxides are not
reduced by hydrogen
iron(II) oxide
lead(II) oxide
copper(II) oxide
silver oxide
heated metal oxides are reduced
by hydrogen
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Effect of Heat on Metal Carbonates:
Thermal Stability & Reactivity
Most carbonates decompose when heated strongly
to produce a metal oxide and carbon dioxide gas.
The ease of decomposition depends on the position
of the metal in the reactivity series.
Recall the reactivity series.
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Thermal Stability of Metal Carbonates
Metal Carbonate Effect of HeatPotassium Carbonate Stable to heat
No visible reactionSodium Carbonate
Calcium Carbonate Decomposes into metal oxide and carbon dioxide
Magnesium Carbonate
Zinc Carbonate
Iron (III) Carbonate
Lead Carbonate
Copper(II) Carbonate
Silver Carbonate Decomposes into silver and carbon dioxide
Metal Metal Oxide + Carbon Dioxide
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Reactions with water & dilute acids:
More vigorous reaction Higher in the reactivity series The metal is more reactive
Reaction with metal carbonates:
The more stable the metal carbonate is toheat, the higher it is in the reactivity series.
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Class Activity & Discussion
Check this out!
http://www.chem.iastate.edu/group/Greenbowe/se
ctions/projectfolder/flashfiles/redox/home.html
http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/redox/home.htmlhttp://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/redox/home.htmlhttp://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/redox/home.htmlhttp://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/redox/home.html -
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So, what have you learnt today?
Displacement Reaction They are redox reactions.
A more reactive metal can displace a less reactive
metal, from its solution or metallic oxide.
Carbonates: Thermal stability & reactivity
The more stable the metal carbonate is to heat,
the higher it is in the reactivity series.