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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.