Oxidation of Manganese

Chemistry and homework help forum.

Organic Chemistry, Analytical Chemistry, Biochemistry, Physical Chemistry, Computational Chemistry, Theoretical Chemistry, High School Chemistry, Colledge Chemistry and University Chemistry Forum.

Share your chemistry ideas, discuss chemical problems, ask for help with scientific chemistry questions, inspire others by your chemistry vision!

Please feel free to start a scientific chemistry discussion here!

Discuss chemistry homework problems with experts!

Ask for help with chemical questions and help others with your chemistry knowledge!

Moderators: Xen, expert, ChenBeier

Post Reply
montinho
Jr. Member
Jr. Member
Posts: 7
Joined: Sun Sep 18, 2011 8:19 pm

Oxidation of Manganese

Post by montinho »

Alright I am doing a lab about oxidation of manganese I need to find the products of these reactants and balance the chemical equation. This is what I have.


[b]THIS CHART[/b]
[u]Compound [/u] [u]Oxidation # of Mn[/u]
KMnO4------------------+7
K2MnO4-----------------+6
MnO2--------------------+4
MnSO4-------------------+2
MnCl3--------------------+3


1.)KMnO4+H2SO4+NaHSO3-->

2.)KMnO4+NaOH+NaHSO3-->

3.)KMnO4+NaHSO3---->

4.) KMnO4 + EDTA + MnSO4(s)---->

what role did EDTA play in this reaction?
montinho
Jr. Member
Jr. Member
Posts: 7
Joined: Sun Sep 18, 2011 8:19 pm

Post by montinho »

post please!
expert
Distinguished Member
Distinguished Member
Posts: 1623
Joined: Sun Feb 22, 2009 8:08 pm

Post by expert »

Did you try it at all?
Here are some clues
1.)KMnO4+H2SO4+NaHSO3--> MnSO4, S(4+)--> S(6+)

2.)KMnO4+NaOH+NaHSO3--> K2MnO4; S(4+)--> S(6+)

3.)KMnO4+NaHSO3----> MnSO4, S(4+)--> S(6+)

4.) KMnO4 + EDTA + MnSO4(s)----> MnO2; EDTA as an acid

what role did EDTA play in this reaction?
Remember safety first! Check MSDS and consult with professionals before performing risky experiments.
montinho
Jr. Member
Jr. Member
Posts: 7
Joined: Sun Sep 18, 2011 8:19 pm

Post by montinho »

k i have the following, could you please tell me if I am correct?

1) H++2KMnO4(aq)+H2SO4(aq)+5NaHSO3(aq)->2MnSO4(aq)+5K2SO4(aq)+NaSO4(aq)+3H2O

2)
2KMnO4(aq)+3NaOH(aq) + NaHSO3(aq) -> K2SO4 +2K2MnO4(aq) + 2Na2SO4(aq) + 2H2O

3)
2KMnO4 + 3NaHSO3 -> 2MnO2(s)+ K2MnO4 (aq) + 3Na2SO4(aq) + H+ + H2O
expert
Distinguished Member
Distinguished Member
Posts: 1623
Joined: Sun Feb 22, 2009 8:08 pm

Post by expert »

1) H++2KMnO4(aq)+H2SO4(aq)+5NaHSO3(aq)->2MnSO4(aq)+5K2SO4(aq)+NaSO4(aq)+3H2O

H+ already comes from H2SO4; NaSO4 incorrect: Na2SO4 correct
2)
2KMnO4(aq)+3NaOH(aq) + NaHSO3(aq) -> K2SO4 +2K2MnO4(aq) + 2Na2SO4(aq) + 2H2O

correct

3)
2KMnO4 + 3NaHSO3 -> 2MnO2(s)+ K2MnO4 (aq) + 3Na2SO4(aq) + H+ + H2O
Incorrect. K2MnO4 forms only at basic conditions. Here you generate acid. Depends on the amount of reagents the outcome is MnO2 or MnSO4 or both
Remember safety first! Check MSDS and consult with professionals before performing risky experiments.
expert
Distinguished Member
Distinguished Member
Posts: 1623
Joined: Sun Feb 22, 2009 8:08 pm

Post by expert »

Remember safety first! Check MSDS and consult with professionals before performing risky experiments.
montinho
Jr. Member
Jr. Member
Posts: 7
Joined: Sun Sep 18, 2011 8:19 pm

Post by montinho »

so is 1 like this?

2KMnO4 + H2SO4 + 5NaHSO3 -> 2MnSO4 + 5K2SOR + Na2SO4 + 3H2O

??

and for 3, what should the other products be then? I know in this reaction MnO2 (s) is yielded for sure.
expert
Distinguished Member
Distinguished Member
Posts: 1623
Joined: Sun Feb 22, 2009 8:08 pm

Post by expert »

What is K2SOR?

4 KMnO4 + H2SO4 + 10 NaHSO3 = 4 MnSO4(aq) + 2 K2SO4 + 5 Na2SO4 + 6 H2O

That's it!
Last edited by expert on Mon Sep 19, 2011 9:02 pm, edited 1 time in total.
Remember safety first! Check MSDS and consult with professionals before performing risky experiments.
montinho
Jr. Member
Jr. Member
Posts: 7
Joined: Sun Sep 18, 2011 8:19 pm

Post by montinho »

[quote="expert"]What is K2SOR?[/quote]
K2SO4**
expert
Distinguished Member
Distinguished Member
Posts: 1623
Joined: Sun Feb 22, 2009 8:08 pm

Post by expert »

Incorrect
Correct is
4 KMnO4 + H2SO4 + 10 NaHSO3 = 4 MnSO4 + 2 K2SO4 + 5 Na2SO4 + 6 H2O

Use this tool if lazy http://www.webqc.org/balance.php
Remember safety first! Check MSDS and consult with professionals before performing risky experiments.
montinho
Jr. Member
Jr. Member
Posts: 7
Joined: Sun Sep 18, 2011 8:19 pm

Post by montinho »

and so what about number 3? i know one of the products is MnO2 (s), i'm sort of lost on this question.
expert
Distinguished Member
Distinguished Member
Posts: 1623
Joined: Sun Feb 22, 2009 8:08 pm

Post by expert »

Write the reaction with a single Mn-product MnO2, not MnO2 and MnSO4

If you want MnSO4 then write witha single Mn-product MnSO4

Then if you need both, add one equation to the other.
Remember safety first! Check MSDS and consult with professionals before performing risky experiments.
montinho
Jr. Member
Jr. Member
Posts: 7
Joined: Sun Sep 18, 2011 8:19 pm

Post by montinho »

so is this correct?

2KMnO4 + 3NaHSO3 -> 2MnO2(s) + 3Na2SO4(aq) + H+ + H2O

??
Post Reply