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moongazer
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K2Cr2O7 + S8 > K2O + Cr2O3 + SO2
(the numbers are subscripts)
find the oxidation number
 2 years ago
 2 years ago
moongazer Group Title
K2Cr2O7 + S8 > K2O + Cr2O3 + SO2 (the numbers are subscripts) find the oxidation number
 2 years ago
 2 years ago

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Callisto Group TitleBest ResponseYou've already chosen the best response.2
Oxidation number of ..?
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
all elements there
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
K > Group I metal. Either 0, or +1. Here, it's an ion. So, what is the oxidation number of K?
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Btw, I think it's K2Cr2O7 on the left?
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
yes, there is a typo :)
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Okay. What have you got for K?
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
could you check my answers?
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
I'll just post it :)
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Yup. For both sides, there is no oxidation number change for K. So, K on both sides are +1. Sure :)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
I'll just answer it :)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
Isn't it that if the subscript of O is greater than 2, it will have an oxidation number of 2 ?
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
O has an oxidation number of 2  You're right! :)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
but if "O" only it will have 1 and O2 it will have 0?
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
No, not really. O is in group 6, it need 2 more electrons. So, usually, its oxidation number is 2 when it is bonded to other atoms. If it is an element (i.e. O2), its oxidation number is 0 as element in its own form. But remember, it's just 'usually' when its oxidation number is of 2. There are some exceptions. For instance, if I remember correctly, O in F2O is +2 since F is a more electronegative element and it has an oxidation number of 1. Since there are two F, oxidation number of O has to be +2 in order to get a net oxidation number of the compound equal to zero.
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
ohh, thanks for the info. Here are my answers :) K2(+1)Cr2(+6)O7(2) + S8(0) > K2(+1)O(2) + Cr2(+3)O3(2) + S(0)O2(0) The oxidation number is enclosed by parenthesis.
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
Is it correct ?
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Almost. S(0)O2(0) < not correct (for both)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
K2(+1)Cr2(+6)O7(2) + S8(0) > K2(+1)O(2) + Cr2(+3)O3(2) + S(2)O2(+1)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
I made the oxidation number of O2 the unknown. Is it correct now?
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Not really. For SO2, O is 2 (you can take a look at O first as it is more electronegative than S!) O2 is NOT an element in this case, so O doesn't have a oxidation number of 0!
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
K2(+1)Cr2(+6)O7(2) + S8(0) > K2(+1)O(2) + Cr2(+3)O3(2) + S(+4)O2(2) I think this is correct already :)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
I'll say something. I'll just fix the laptop :)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
please wait :)
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Take your time!
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
Whew! The battery almost got dead. It keeps on saying plugged in, not charging.
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
So it means, If you have a molecule with an oxygen,to find the oxidation number of the elements in it. You will identify first the more electronegative element and made the charge of it equal to its oxidation number. Then make the oxidation number of the other element the unknown.
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
you will solve for the unknown oxidation number
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Hmm.. you can say so. But when you consider electronegativity of the element, that would be talking about the group V  group VII For metal, it usually has positive oxidation number. If I remember correctly, for group I metal, when it does not exist in element state, it should be of an oxidation number of +1, and looks like it works for most of the group II metal too. But for transition metals, that's another case...
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
One little practice for you (if you want one lol) Find the oxidation number of H, O and Cl in the compound HOCl.
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
H(+1)O(2)Cl(+1)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
I hope it is correct. :)
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
Yey! thanks!
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Welcome :)
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
There are three definitions....
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
is it the loss of electrons and reactions directly with O2 ?
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
transfer of electrons?
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
Definition of oxidation: 1. addition of oxygen to a substance 2. a process in which a substance loses electrons 3. a process in which the oxidation number of an element in a substance increases.
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
and reduction is the opposite of that?
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
In my notes it says below oxidation it says: +O H What does "H" have to do with oxidation and reduction ?
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
idk I just saw in my notes. I was late during our class so I didn't know what is H there
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
Anyway, thank you very much in your time and effort helping me. :)
 2 years ago

Callisto Group TitleBest ResponseYou've already chosen the best response.2
You're welcome.. Sorry that I couldn't help :(
 2 years ago

moongazer Group TitleBest ResponseYou've already chosen the best response.1
It's alright you helped me a lot. :)
 2 years ago
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