Activity series
Experiment # 15
What we are doing today:
• We are going to test reactions of metals with acids
• We are going to test single replacement reactions.
•We are going to determine a relative activity series BASED
ON OUR EXPERIMENTAL DATA
9F Reactivity in chemistry
What does reactivity mean?
Elements that are reactive readily take part in
reactions with other chemicals.
To compare the reactivity of different elements,
we might see how easily they react with oxygen.
Some metals corrode in
minutes out on the bench.
Others take longer to corrode,
unless you heat them.
9F The Gold Cup again?
We can list metals in order of
how quickly they react with
oxygen.
This ranking of metals
according to reactivity is called
the reactivity series.
Ca
Element Reactivity
Li
Rb
K
Ba
Ca
Na
Mg
Al
Mn
Zn
Cr
Fe
Ni
Sn
Pb
H2
Cu
Hg
Ag
Pt
Au
Halogen Reactivity
F2
Cl2
Br2
I2
9F Reaction of metals with acid
What if we react different metals with acid?
copper
iron
lead
magnesium
sodium
–– the
the
–– no
the
metal
metal
–bubbles,
metal
the
reacts
reacts
metal
bursts
no
slowly,
very
reacts
reaction
into
slowly,
producing
flames,
quickly
with
producing
acid
with
a very
a few
thestrong
very
bubbles
acid,few
reaction
bubblesproducing lots of bubbles
9F Feeling a bit displaced?
A single replacement reaction
happens when one metal replaces
another one in a compound.
Magnesium is more reactive
than copper.
Magnesium displaces copper
from copper sulphate solution.
magnesium + copper sulphate
magnesium sulphate + ?
9F A model for displacement reactions
This model will help explain displacement reactions.
Think of reactivity as aggression!
Write a word equation for this reaction.
Activity series
• The higher up in the
chart, the more reactive
the metal.
• Only metals higher on
the chart can displace a
metal below it
Fe II (s) + 2CuSO4 (aq)
2Cu(s) + Fe(SO4)2 (aq)
Element Reactivity
Li
Rb
K
Ba
Ca
Na
Mg
Al
Mn
Zn
Cr
Fe
Ni
Sn
Pb
H2
Cu
Hg
Ag
Pt
Au
Halogen Reactivity
F2
Cl2
Br2
I2
Part A
• To six test tubes add approximately 0.5 ml
of HCl
• Add a small piece Ca metal to the test tube
• Record all changes
• Repeat for all five metals
• Write complete and ionic equations for each
metal
Part B
• To one test tube add approximately 0.5 ml of a
polyatomic ionic compound Ca(NO3)2
• Repeat for each of the other six polyatomic ionic
compounds
• Add a small piece Ca metal to each test tube
• Record all changes
• Repeat for all five metals
• Write complete and ionic equations for each metal
Part B
• Dispose of the waste and Repeat all
procedures for each of the other five metals
• Write complete and net ionic equations for
each metal
Part C
Based on your experimental data determine a relative activity
series of the metals in question
Ca
Cu
Fe
Mg
Sn
Zn
Al
Types of chemical equations
Equations can be divided into 3 types
1) Molecular, 2) Ionic, 3) Net ionic
• Here is a typical molecular equation:
Cd(NO3)2(aq) + Na2S(aq)  CdS(s) + 2NaNO3(aq)
• We can write this as an ionic equation
• (all compounds that are (aq) are written as
ions):
Cd2+(aq) + 2NO3–(aq) + 2Na+(aq) + S2–(aq)
 CdS(s) + 2Na+(aq) + 2NO3–(aq)
Net Ionic equations
Cd2+(aq) + 2NO3–(aq) + 2Na+(aq) + S2–(aq)
 CdS(s) + 2Na+(aq) + 2NO3–(aq)
• To get the NET ionic equation we cancel out
all terms that appear on both sides:
Net:
Cd2+(aq) + S2–(aq)  CdS(s)
Equations must be balanced
• There are two conditions for molecular, ionic,
and net ionic equations
Materials balance
Both sides of an equation should have the
same number of each type of atom
Electrical balance
Both sides of a reaction should have the same
net charge
Due next week
• Pg 167 and 168
• Need to show all work for full credit!!