RedOx Lab

1
RedOx Lab

• Need 6 groups to prepare solutions
• Each group will prepare 50mL of a 0.1M solution
• Solid sample or Stock solution ?????
• Make your calculations and check them with Mr.
  Bookwalter
• Clean and fill reagent bottles with your solution

MgSO4 CuSO4 AgNO3
ZnSO4 FeSO4 H2SO4
2
Results Bookwalter
NR Gas NR
NR NR NR NR NR
Gas NR
NR Gas NR NR
3
RedOx reactions(Single Replacement)

• 2 Mg (s) O2 (g) ? 2 MgO (s)

0
0
2
-2
Mg oxidized ? more positive
(reducing agent)
O2 reduced ? more negative
(oxidizing agent)
4
Oxidation of Metals by Acids and Salts

• Zn (s) 2 HCl (aq) ? ZnCl2 (aq) H2 (g)

0
1
2
0
Zn oxidized ? more positive
(reducing agent)
H reduced ? more negative
(oxidizing agent)
5
Oxidation of Metals by Acids and Salts

• H2SO4 (aq) Fe (s) ? FeSO4 (aq) H2 (g)

1
0
2
0
Fe oxidized ? more positive
(reducing agent)
H reduced ? more negative
(oxidizing agent)
6
Oxidation of Metals by Acids and Salts

• Ni(NO3)2 (aq) Fe (s) ? Ni (s) Fe(NO3)2
  (aq)
• Net Ionic

2
0
0
2
Ni2 (aq) Fe (s) ? Ni (s) Fe2 (aq)
Fe oxidized ? more positive
(reducing agent)
Ni reduced ? more negative
(oxidizing agent)
7
Activity Series

• Use to predict if a reaction will occur
• Single Replacement
• Any metal can be OXIDIZED by any metal below it
  on the series

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Examples

• Cu (s) 2AgNO3 (aq) ? Cu(NO3)2 (aq) 2 Ag
  (s)
• Net Ionic

0
1
2
0
Cu (s) 2Ag1(aq) ? Cu2 (aq) 2Ag(s)
Cu oxidized ? more positive
(reducing agent)
Ag reduced ? more negative
(oxidizing agent)
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Examples

• Cu (s) 2FeNO3 (aq) ? No Reaction

Based on the Activity Series Cu cant be oxidized
by Fe
Meaning that Cu is below Fe on the activity series
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Examples

• Ni (s) 2 HCl (aq) ? NiCl2 (aq) H2 (g)
• Net Ionic

0
1
2
0
Ni (s) 2H1(aq) ? Ni2 (aq) H2 (g)
Ni oxidized ? more positive
(reducing agent)
H reduced ? more negative
(oxidizing agent)
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Types of RedOx reactions

• Single replacement in acid
• Mg(s) HCl(aq) ?
• Single replacement in H2O
• Ca(s) H2O(l) ?
• Single replacement in aqueous salt
• Cu(s) AgNO3(aq) ?
• Single replacement of nonmetals
• F2(g) LiBr(aq) ?

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E. Solution Stoichiometry and Titrations

• 1. Stoichiometry
• Ex. How many grams of H2O form when 25.0 mL of
  0.100M HNO3 is neutralized by NaOH?

0.100 mole HNO3 0.025 L 2.5 x 10-3 mole HNO3
L
2.5 x 10-3 mole
X grams
0.045 grams H2O
HNO3(aq) NaOH (aq) ? H2O(l) NaNO3 (aq)
1 mole
1 mole

18 grams
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2. Titrations

• Use a known standard solution to react with an
  unknown concentration of solution.
• Equivalence point same of moles of each
  reactant
• Indicator a chemical that determines the end
  point of reaction (Ie. Equivalence point)
• The indicator will change color
• Phenolphtalein
• CLEAR ACID RED BASE

The end point is neutralized!!!