1. Define displacement reaction.
2. Predict what will happen when:
a) Magnesium is put into Silver
Nitrate solution
b) Zinc is put into Magnesium
Nitrate solution
3. Write down the symbol equation for
the reaction between Calcium metal
and Lead Nitrate solution
What’s the difference between an
“element” and an “ion”?
When two solutions, Barium Nitrate and
Sodium Hydroxide are mixed, the
solution turns cloudy/milky – which
indicates that precipitate has been
formed.
a) Write down the word equation for
this reaction
b) Write down the symbol equation for
this reaction
Displacement Reaction
It is a type of reaction which an element
(or ion) replaces another element (or ion)
in a compound.
A + BC → B + AC
Notice how ‘B’ has been replaced by ‘A’
Example ONE:
Silver Nitrate & Copper
When a piece of copper reacts with silver
nitrate solution, the copper replaces the
silver, producing copper nitrate and silver.
Word equation:
Symbol equation:
Precipitation Reaction
(a.k.a. double exchange reaction)
AB + CD → AD
+ CB
BaNO3 + NaOH → Ba(OH)2 + NaNO3
Displacement Reaction
(a.k.a. single exchange reaction)
A + BC
→ B +
AC
Cu + AgNO3 → Ag + Cu(NO3)2
Example TWO:
Copper Sulfate & Magnesium
When a piece of magnesium is dropped
into copper sulfate solution, the
magnesium replaces the copper,
producing magnesium sulfate and copper.
Word equation:
Symbol equation:
Practical: Displacement Reaction
between Magnesium and Copper Sulfate
•
Method: Drop a piece of magnesium
ribbon into about 50 ml of copper
sulfate solution in a beaker.
•
Result:
•
Word Equation:
•
Symbol Equation:
Displacement Reaction
It is a type of reaction which an element
(or ion) replaces another element (or ion)
in a compound.
A + BC → B + AC
Notice how ‘B’ has been replaced by ‘A’
Displacement Reaction
It is a type of reaction which an element
(or ion) replaces another element (or ion)
in a compound.
WHY?
Bob = Copper
Lara = Sulfate
Nick = Magnesium
• Lara ditches Bob because she
finds Nick more attractive. (i.e.
Nick ‘replaces’ Bob)
• In chemistry,
“Attractive” means
“Reactive”.
Reactivity
Series of
Metals
Can you explain why
magnesium replaces
copper in copper
sulfate solution?
What would happen…?
Zinc + Copper sulfate → ???
Iron + copper sulfate → ???
Silver + copper sulfate → ???
Gold + + copper sulfate → ???
Practical: Displacement Reaction
between Zinc / Iron and Copper Sulfate
1. Add some zinc granules to about 50 ml
of copper sulfate solution in a test
tube.
2. Write down the result, word equation
and balanced symbol equation
3. Repeat the whole experiment, using
iron fillings instead of zinc granules
Practical: Reactivity Series
Method:
1. In five test tubes, put about 5 ml of
copper sulfate soultion.
2. Put a piece of copper, zinc, tin, lead
and magnesium into the test tubes.
Prediction: Which will react and which
will NOT react? Why and why not?
•
Write down the result
•
Write down the word equations
AND the balanced symbol
equations for the reactions that
did take place.
Practical: Reactivity Series 2
Task - create your own reactivity series
Copper Iron
Copper
sulfate
Iron sulfate
Lead nitrate
Magnesium
sulfate
Zinc sulfate
Lead
Magnesium Zinc