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