CHM 2045C REDOX Challenge Contest Pre-Lab Report

 

Name________________________________  Date____________

Write and balance 8 of the Acid Media and 8 of the Basic Media Redox Equations. Show the coefficients for these 16 reactions on this page, but neatly show all work for each equation either in your lab manual or on separate paper. Attach this work to this page and submit before the Contest begins the week of July 19, 2010:

Reference McMurry Chapter 4, Sections 4.3, 4.6, 4.7, 4.10

 

Ion-Electron Method or Half Equation Method (McMurry 4.10)

 

Acid Media: ((Select 4 of the 7 Net Ionic Equations)

 

Zn      +       NO3 1-   +     H 1+      à   Zn 2+    +   NH4 1+     +    H2O

 

MnO4 1-   +   C2O4 2-  +   H 1+      à    Mn 2+   +   CO2         +    H2O

 

Cr2O7 2-   +   C2H5OH  +   H 1+   à    Cr 3+   +   HC2H3O 2     +    H2O

 

SO4 2-     +     CH2O     +   H 1+     à    H2S     +   CO2         +    H2O

 

FeS   +       NO3 1-   +     H 1+        à   NO   +   Fe 2+    +   SO4 2-     +    H2O

 

Cr2O7 2-   +   Cl 1-   +     H 1+        à   Cr 3+   +   Cl2     +    H2O

 

H2O2   +   MnO4 1-   +     H 1+        à   Mn 2+   +   O2         +    H2O

 

((Select 4 of the 8 Total Molecular Equations)

 

MnO    +    PbO2   +   HNO3    --->    HMnO4  +   Pb(NO3)2 +   H2O

 

 

Na2HAsO4  +  KBrO3   +  HCl  --->   NaCl  +  KBr   +   H3AsO4

 

 

WO3    +   SnCl2   +    HCl   --->    W3O4   +    H2SnCl6   +    H2O

 

 

As2S5   +  HNO3    ---->     H3AsO4  +   NaHSO4  +    NO2  +   H2O

 

 

CuS   +  HNO3   ---->   Cu(NO3)2   + S    +   NO    +  H2O

 

 

Na2C2O4 + KMnO4 +  H2SO4  --->  K2SO4 +  Na2SO4 +  MnSO4 + CO2  +H2O

 

 

U(SO4)2  +  KMnO4  +  H2O --->  H2SO4  +  K2SO4  +  MnSO4  +  UO2SO4

 

 

CdS  +  I2  HCl   --->   CdCl2   +   HI   +   S

 

Basic Media  (Work four of the five) Net Ionic Equations

 

Cr 3+         +       ClO3 1-   +     OH 1-      à   CrO4 2-  +   Cl 1-     +    H2O

 

 

Bi2O3  + OH 1-  + OCl 1-  à  BiO3 1-  + Cl 1-  H2O

 

 

Mn 2-        +        Br2          +   OH 1-      à    MnO2   +   Br 1-     +    H2O

 

 

Fe(OH)2    +       O2         +    H2O         à    Fe 3+       +   OH 1-     

 

 

MnO4 1-     +     C2O4 2-    +    OH 1-     +  H2O   à     MnO2    +    CO3 2-

 

 

Work four of the following: Total Molecular Equations

 

Zn           +     NaNO3      +   NaOH      à    Na2ZnO2   +     NH3     +   H2O

 

Ag  +  KCN-  +  O2  +  H2O  à  KAg(CN)2   +  KOH

 

 

CoCl2  +  Na2O2  +  NaOH  +  H2O  --->  Co(OH)3  + NaCl

 

 

K3Fe(CN)6   +  Cr2O3  +  KOH   --->  K4Fe(CN)6  +  K2CrO4   +  H2O

 

 

N2H4         +    O2           à     N2          +   H2O2      (basic solution)

 

 

AsO2 1-       +    ClO 1-      à    AsO3 1-   +    Cl 1-     (basic solution)

 

 

 

Neutral Media (No H 1+ or OH 1- Ions Present)

 

The last two below are  required, so give them a try!

 

Ca3(PO4)2    +   SiO2   +  C    à    CaSiO3      +   P4        +   CO

 

Cu(NH3)4Cl2 + KCN + HOH ---> NH3 + NH4Cl + K2Cu(CN)3 +   KCNO    +   KCl  

 

 

Homework for the Most Advanced Students:

(These Equations are part of the contest beyond Round 12)

 

Neutral Media:

 

Cu(NH3)4Cl2 + KCN + HOH ---> NH3 + NH4Cl + K2Cu(CN)3 +   KCNO    +   KCl  

 

 

 

 

half equation:

 

 

 

 

half equation:

 

 

 

 

 

Acid  Media

 

 CoCl2 + KNO2   + HC2H3O2  ----> K3Co(NO2)6   + NO +   KC2H3O2   + KCl   + HOH

 

 

half equation:

 

 

 

half equation:

 

 

 

 

 

Basic Media

 CrI3 + KOH   +   Cl2   ---->   K2CrO4    +   KIO4     +    KCl       +    HOH

 

half equation:

 

 

 

 

half equation:

 

 

 

 

 

The following are deemed the hardest REDOX Equations to balance in the world

 (Extra Credit-You must show your work and use Ion-Electron):

Daughter of All REDOX Equations:
HIO3 + FeI2 + HCl ---> FeCl3 + ICl + HOH
(A hint: the coefficients of the daughter equation will add up to 66)


 

 

 

Son of All REDOX Equations:
CuSCN + KIO3 + HCl ---> CuSO4 + KCi + HCN + ICl + HOH


 

 

 

 

Father of All REDOX Equations:
NH4ClO4 + Al ---> HCl + Cl2 + NO + AL2O3 + HOH


 

 

 

 

Mother of All REDOX Equations:
[Cr(N2H4CO)6]4[Cr(CN)6]3 + KMnO4 + H2SO4 --->

 

                   K2Cr2O7 + MnSO4 + CO2 + KNO3 + K2SO4 + HOH