help with this chemistry oxidation number question please!!

Watch
GalInSixthForm
Badges: 12
Rep:
?
#1
Report Thread starter 1 year ago
#1
decomposition of H202:

H202 -> H20 + 02

Apparently, oxidation number of oxygen at the start of the reaction is -1. why?? shouldn't it be -2??
0
reply
tuxedo-
Badges: 11
Rep:
?
#2
Report 1 year ago
#2
The rule we were taught is that oxygen is always -2 oxidation state except in a peroxide. So in H2O2 it is -1. This is fairly simple to get since H tends to be a +1 oxidation state so to balance it to 0 it makes sense.
0
reply
Sim0nbo55
Badges: 8
Rep:
?
#3
Report 1 year ago
#3
(Original post by GalInSixthForm)
decomposition of H202:

H202 -> H20 + 02

Apparently, oxidation number of oxygen at the start of the reaction is -1. why?? shouldn't it be -2??
Oxidation number for 0 in peroxides is always -1
0
reply
Ðeggs
Badges: 22
Rep:
?
#4
Report 1 year ago
#4
No there are exceptions. Consider potassium superoxide KO2 where the oxidation state of oxygen is -1/2!
In hydrogen peroxide the oxidation state of O is -1.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Do you think receiving Teacher Assessed Grades will impact your future?

I'm worried it will negatively impact me getting into university/college (46)
37.7%
I'm worried that I’m not academically prepared for the next stage in my educational journey (12)
9.84%
I'm worried it will impact my future career (5)
4.1%
I'm worried that my grades will be seen as ‘lesser’ because I didn’t take exams (29)
23.77%
I don’t think that receiving these grades will impact my future (20)
16.39%
I think that receiving these grades will affect me in another way (let us know in the discussion!) (10)
8.2%

Watched Threads

View All
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise