The Student Room Group

Oxidation number format vs ion charge format

Is there a specific standard to differentiate the difference between how you write the subscript number for both ions and oxidation states?

I saw in a video that ions are written, for example, Ca^2+ and oxidation state SO₄^-²

So the number and sign were the opposite way around.
(edited 4 months ago)
Reply 1
its always number then charge, no matter if its a formal charge or an oxidation state, they are both superscripts
Reply 2
Original post by Scanjo63
its always number then charge, no matter if its a formal charge or an oxidation state, they are both superscripts

Okay, thank you for confirming.
Original post by KingRich
Is there a specific standard to differentiate the difference between how you write the subscript number for both ions and oxidation states?
I saw in a video that ions are written, for example, Ca^2+ and oxidation state SO₄²-
So the number and sign were the opposite way around.

The oxidation number is a NUMBER, which may be positive or negative, so it should be written as -2, +3 etc.
The ionic charge is the magnitude of the positive or negative charges and should be written as 2+, 3- etc.
In some specifications you will lose a mark for getting it the wrong way round.
Original post by Scanjo63
its always number then charge, no matter if its a formal charge or an oxidation state, they are both superscripts

incorrect
Reply 5
Original post by charco
The oxidation number is a NUMBER, which may be positive or negative, so it should be written as -2, +3 etc.
The ionic charge is the magnitude of the positive or negative charges and should be written as 2+, 3- etc.
In some specifications you will lose a mark for getting it the wrong way round.
I see, so the person who commented before you is wrong. My original OP is correct based on what was stated in the video I watched. (I just noticed I miswrote the oxidation number, so I have corrected it as before it was the same format as the ion charge)

I ask because I am doing an assignment, and I have been asked to give the oxidation states of the following(see photo) they’ve been presented as ionic charges. If I understand correctly, a redox reaction transfers electrons between atoms, compounds or ions. Hence, my confusion in regards to the layout.

If my understanding is correct:
IMG_0172.jpeg

The attached image here shows ionic charges but should they be Fe^+3 to represent an oxidation state? I hope I make sense in what I am asking!
(edited 4 months ago)
Original post by KingRich
I see, so the person who commented before you is wrong. My original OP is correct based on what was stated in the video I watched. (I just noticed I miswrote the oxidation number, so I have corrected it as before it was the same format as the ion charge)
I ask because I am doing an assignment, and I have been asked to give the oxidation states of the following(see photo) they’ve been presented as ionic charges. If I understand correctly, a redox reaction transfers electrons between atoms, compounds or ions. Hence, my confusion in regards to the layout.
If my understanding is correct:
IMG_0172.jpeg
The attached image here shows ionic charges but should they be Fe^+3 to represent an oxidation state? I hope I make sense in what I am asking!

The layout is correct.
Ionic charges are the magnitude of the charge eg. 2+
The oxidation number is a number eg +2, or simply 2
Reply 7
Original post by charco
The layout is correct.
Ionic charges are the magnitude of the charge eg. 2+
The oxidation number is a number eg +2, or simply 2

Okay, thanks.

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