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Reply 1

laithalissa
Can somebody give me the balanced equation for the titration of:

hydrated iron (II) sulphate (dissolved in H2SO4) + Potassium permanganate

please.

My assumption is that

MnO4 + 5 Fe(2+) + 8H+ --> Mn(2+) + 5 Fe(3+) + 4 H2O

Thanks in advance


you missed the negative change off MnO4(-) but otherwise OK

Reply 2

correct apart from the missing -ive charge on the MnO

Reply 3

laithalissa
Can somebody give me the balanced equation for the titration of:

hydrated iron (II) sulphate (dissolved in H2SO4) + Potassium permanganate

please.

My assumption is that

MnO4 + 5 Fe(2+) + 8H+ --> Mn(2+) + 5 Fe(3+) + 4 H2O

Thanks in advance


MnO4- + 5Fe2+ + 8H+ ---> 5Fe3+ + Mn2+ + 4H2O

So the only thing wrong was the missing negative charge on the permanganate :smile:

Reply 4

Kinkerz
MnO4- + 5Fe2+ + 8H+ ---> 5Fe3+ + Mn2+ + 4H2O

So the only thing wrong was the missing negative charge on the permanganate :smile:



Great, thanks everyone, but what's happening to the SO4- and K+ (just out of curiosity)?

Reply 5

laithalissa
Great, thanks everyone, but what's happening to the SO4- and K+ (just out of curiosity)?


:hmmmm:

Reply 6

Kinkerz
:hmmmm:


The sulphate from the FeSO4 and the potassium from the KMn04-

Reply 7

laithalissa
The sulphate from the FeSO4 and the potassium from the KMn04-


I knew what you meant :tongue: I just don't know the answer!

Reply 8

spectator ionss - not involved

Reply 9

dunno really my gess is that they act as a catalyst? meaning they dont change in the reaction so therefore arn't featured? :s-smilie:

Reply 10

Kinkerz
I knew what you meant :tongue: I just don't know the answer!

sorry! Thanks for the help earlier, but this part really bugging me, they can't be spectator ions, do can they react with each other? :biggrin:

Reply 11

chemicalguy
spectator ionss - not involved


But surely K+ and SO4- cant exist alone in this solution :s-smilie:

Reply 12

Dweezle
dunno really my gess is that they act as a catalyst? meaning they dont change in the reaction so therefore arn't featured? :s-smilie:

#

Now, now - just cos something doesn't change doesn't make it a catalyst. Its only a catalyst if it increases the rate.

There are always spectator ions present in reactions - the K+ and SO42- are spectator in this case as they have no role in the reaction at all

Rob

Reply 13

Laithalissa - they ARE SPECTATORS

Reply 14

chemicalguy
#

Now, now - just cos something doesn't change doesn't make it a catalyst. Its only a catalyst if it increases the rate.

There are always spectator ions present in reactions - the K+ and SO42- are spectator in this case as they have no role in the reaction at all

Rob

pHD biochem guy wins :biggrin: thanks for the help everyone, VERY helpful.

Reply 15

any idea what the half equations are?

Reply 16

Mali92
any idea what the half equations are?



Fe2+ --> Fe3+ + 1e

MnO4- + 8H+ + 5e --> Mn2+ + 4H2O

Reply 17

How do you balance this equation: KMnO4 + FeSO4 + H2SO4 ------> Fe2(SO4)3 + MnSO4 + K2SO4 + H20

thanks in advance! :smile:

Reply 18

Original post by Lovemonkey
How do you balance this equation: KMnO4 + FeSO4 + H2SO4 ------> Fe2(SO4)3 + MnSO4 + K2SO4 + H20

thanks in advance! :smile:


Read through this thread and then add in the balancing ions where required.

Manganate(VII) needs potassium ions
Hydrogen ions are delivered along with sulfate ions
etc.

Reply 19

Original post by charco
Fe2+ --> Fe3+ + 1e

MnO4- + 8H+ + 5e --> Mn2+ + 4H2O


Can [ Fe2+ -->Fe3+ + 1e ] be [ Fe2+ -->Fe3+ +5e ] or [ 5Fe2+ -->5Fe3+ + 5e ] ? Someone pls explain? :'(