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Chemistry question working out the formula

Please could someone explain what the formula for manganese(IV) sulfate is? Shouldn’t it be Mn(SO4)2 because Mn is 4+ and SO42-
Original post by Ashirs
Please could someone explain what the formula for manganese(IV) sulfate is? Shouldn’t it be Mn(SO4)2 because Mn is 4+ and SO42-

The formula is correct. Watch the below video if you want further clarification.

https://youtu.be/uMSAszbVqbo
Reply 2
Original post by Allera
The formula is correct. Watch the below video if you want further clarification.

https://youtu.be/uMSAszbVqbo


Thank you, so please could you explain why this is different? I have attached it below
Original post by Ashirs
Thank you, so please could you explain why this is different? I have attached it below

Well it seems that Mn has been reduced from +4 to +2. So then yes the equation is correct.
But if it was Manganese(IV)sulfate then it would be Mn(SO4)2, but it is not Manganese(IV)sulfate in the equation.
Reply 4
Original post by Allera
Well it seems that Mn has been reduced from +4 to +2. So then yes the equation is correct.
But if it was Manganese(IV)sulfate then it would be Mn(SO4)2, but it is not Manganese(IV)sulfate in the equation.

Why would it not remain manganese (IV) as nothing has been specified in the question? How could I tell that it should be reduced? Thank you!
Well if you look at the oxidation numbers you would notice that Mn has been reduced. I need to know the exam question before I can answer your question.
Reply 6
Original post by Allera
Well if you look at the oxidation numbers you would notice that Mn has been reduced. I need to know the exam question before I can answer your question.

Here is the exam question it is part iv
Well the question is asking to underline which element is being reduced so Mn is being reduced from +4 to +2. I don't quite understand what your question is, so if you could reword it. I could try and answer it again.
Reply 8
Original post by Allera
Well the question is asking to underline which element is being reduced so Mn is being reduced from +4 to +2. I don't quite understand what your question is, so if you could reword it. I could try and answer it again.

Sorry, although the question says something is being reduced, how do we know that manganese is being reduced? I understand that manganese sulfate is one of the products but why wouldn’t it just remain as manganese 4+, how do we know it is that element that is being reduced?
Sorry if this is still confusing, thank you for explaining it before anyways!
Original post by Ashirs
Sorry, although the question says something is being reduced, how do we know that manganese is being reduced? I understand that manganese sulfate is one of the products but why wouldn’t it just remain as manganese 4+, how do we know it is that element that is being reduced?
Sorry if this is still confusing, thank you for explaining it before anyways!

So this is a redox reaction. We would find out which elements are being oxidised and reduced by writing and comparing the oxidation numbers of all the elements. I have tried to show how I did it in the attachment below.
So Mn is reduced going from +4 to +2
O is oxidised from +4 to +6
So I know that Mn is +2 in the products because the overall charge of MnSO4 is 0. If Mn was +4 in the products it would be MnSO4^2+, which it isn't.
Reply 10
Original post by Allera
So this is a redox reaction. We would find out which elements are being oxidised and reduced by writing and comparing the oxidation numbers of all the elements. I have tried to show how I did it in the attachment below.
So Mn is reduced going from +4 to +2
O is oxidised from +4 to +6
So I know that Mn is +2 in the products because the overall charge of MnSO4 is 0. If Mn was +4 in the products it would be MnSO4^2+, which it isn't.

Ok thank you!
Original post by Ashirs
Ok thank you!

welcome :smile:

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