Post on 04-Jan-2016
description
Bula!
Do Now…
Discuss topics that are on tomorrow’s quiz.
HW…
Read 7.3, #’s 22-24,26-30 & study for quiz
Ions in Aqueous Solution
Pb(NO3)2(s) Pb(NO3)2(aq)
Pb2+(aq) + 2 NO31–(aq)
addwater
dissociation:
Pb2+
NO31–
NO31–
Pb2+
NO31–
NO31–
“splitting into ions”
NaI(s) NaI(aq)
Na1+(aq) + I1–(aq)
Na1+ I1– Na1+ I1–add
water
= cations (+) = anions (-)
Check new combinations to decide!
(?)
For double-replacement rxns(or precipitate rxns),The reaction will occur if any product is: water a gas a precipitate
driving forces
_ Pb(NO3)2(aq) + _ K2SO4(aq)
_ FeCl3(aq) + _ Cu(NO3)2(aq)
Fe3+ Cl1– NO31–
Pb2+ NO31– K1+ SO4
2- Pb2+ NO31– K1+ SO4
2- (?)
Cu2+ Cl1–
Cu2+ (?)
Fe3+ NO31– (?)
(ppt) (aq)
(aq) (aq)
NR
_ PbSO4(s) + _ KNO3(aq) 1 1 1 2
= cations (+) = anions (-)
precipitate: a solid product that formsin an aqueous reaction
Na2CO3(aq) + Ca(NO3)2 (aq) CaCO3(s) + 2NaNO3(aq)
2Na1+(aq) + CO32– (aq) + Ca2+(aq) + 2NO3
1–(aq)
clearNa2CO3
solution
clearCa(NO3)2
solution
cloudy solutioncontaining CaCO3(s)
and NaNO3(aq)
= cations (+) = anions (-)
CaCO3(s) + 2Na1+ (aq) + 2NO31–(aq)
CO32– (aq) + Ca2+(aq) CaCO3(s)
COMPLETE IONICEQUATION
NET IONIC EQUATION
SPECTATOR IONS
Mix together ZnSO4(aq) and BaCl2(aq):
ZnSO4 (aq) BaCl2(aq)
Zn2+(aq) + SO42-
(aq) Ba2+(aq) + 2 Cl1–(aq)
Ba2+
Cl1–
Cl1–
Zn2+ SO42-
clear ZnSO4 solution clear BaCl2 solution
Mix them and get the complete ionic equation…
__Zn2+(aq) + __SO42–(aq) + __Ba2+(aq) + __Cl1–(aq)
__BaSO4 (s) + __Zn2+(aq) + __Cl1-(aq)
yields
Cancel spectator ions to get net ionic equation…
__BaSO4(s)1
1 1 1 2
211
Cl1–
Cl1–
__Ba2+(aq) + __SO42– aq) 1 1
Zn2+Ba2+ SO4
2-
Ba2+ SO42-Ba2+ SO4
2-
ppt
In a reaction:
atoms are rearranged
AND mass
energy
charge
are conserved
Balancing Chemical Equations
=law of
conservationof mass
same # of atomsof each type on each
side of equation
Reaction Conditions and Terminology
Certain symbols give important info about a reaction.
(s) = solid
(l) = liquid
(g) = gas
(aq) = aqueous(dissolved in H2O) NaCl(s) NaCl(aq)
More on aqueous…
-- “soluble” or “in solution” also indicate that a substance is dissolved in water (usually)
Other symbols…
means...
Temp. at which we perform rxn. might be given.
The catalyst used might be given.
means ______ is added to the reaction
MgCO3(s) MgO(s) + CO2(g)
C2H4(g) + H2(g) C2H6(g) Pt
C6H5Cl + NaOH C6H5OH + NaCl 400oC
“yields” or “produces”
heat
(i.e., clues about the reaction)
1
How do we know if a reaction will occur?
For single-replacement rxns, use Activity Series.Elements above replace elements below.
_ Ca(s) + _ FeSO4
_ Pb(s) + _ Al2O3 (aq)
_ Fe (s) + _ CaSO4 (aq)
No Reaction
1 1 1
LiKCaNaMgAlZnFePbH+
CuHgAgAu
= cations (+) = anions (-)
1_ Cl2(g) + _ MgBr2(aq) _ Br2 (g) + _ MgCl2 (aq) 1 1 1