Transcript Chemical Reactions

pp. 164 - 169
Single Displacement Reactions
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Single Displacement Reactions occur when
one element replaces another in a compound.
A metal can replace a metal (+) OR
a nonmetal can replace a nonmetal (-).
element + compound product + product
A + BC  AC + B (if A is a metal) OR
A + BC  BA + C (if A is a nonmetal)
(remember the cation always goes first!)
When H2O splits into ions, it splits into
H+ and OH- (not H+ and O-2 !!)
Single Displacement Reactions
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Another view:
Single Displacement Reactions
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Write and balance the following single
displacement reaction equation:
• Zinc metal reacts with aqueous
hydrochloric acid
Zn(s) + 2 HCl(aq)  ZnCl2 + H2(g)
Note: Zinc replaces the hydrogen ion in
the reaction
Activity Series
If you have the correct form of reactants
for a single displacement reaction
(i.e. A + BC  ), this does not mean the
reaction will take place.
 The reactivity of the two elements must
be compared (by using an activity
series); only if the element on the
reactant side is more reactive than its
counterpart will the reaction take place.
 If the reaction doesn’t take place write
“no reaction” following the arrow
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The Activity Series For Metals
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A list of metallic
elements arranged
in order of
decreasing
reactivity.
The greater the
difference in
reactivity, the faster
the reaction will take
place if there is a
reaction.
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Fig. 4 p.165
The Activity Series for
Halogens
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Halogens have their
own activity series.
It is created based
on the principle of
electronegativity
 Recall:
electronegativity
increases from
bottom to top
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Fig. 8 pg.167
Examples:
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NON METAL DISPACEMENT
• Sodium chloride solid reacts with fluorine gas
2 NaCl(s) + F2(g)  2 NaF(s) + Cl2(g)
Note that fluorine replaces chlorine in the compound
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METAL DISPLACEMENT
Aluminum metal reacts with aqueous copper (II)
nitrate
2 Al(s) + 3 Cu(NO3)2(aq)  3 Cu(s) + 2 Al(NO3)3(aq)
Examples Continued:

Predict the products of the reaction, if
any, between iodine and a solution of
sodium chloride. Write the balanced
equation.
Homework:
Read pp. 164 – 169
 Answer p.169 # 2 - 4
