The Student Room Group
O is -2*4 = -8
S is +6

(the overall charge on the SO4 is 2-, so it has to be like this).
Reply 2
calcium878
O is -2*4 = -8
S is +6

(the overall charge on the SO4 is 2-, so it has to be like this).


But surely sulphur is in group 2 and so it must have a charge of -2

And even if the charge on CuSO4(aq) is -2 (which the exam question unhelpfully ommited ), then surely ;

Cu= -2 - ( charge on sulphur + charge on oxygen)

Cu= -2 - (-2 - (4*-2))

Cu= -2 - (-10)

Cu= +8

help!!!!:confused:
Reply 3
In oxidation number questions, only a small number of elements have a fixed oxidation number regardless of where they are on the periodic table. Sulphur isn't one of them :frown:
Oxygen is however, it is always -2.
Reply 4
lanky2610
In oxidation number questions, only a small number of elements have a fixed oxidation number regardless of where they are on the periodic table. Sulphur isn't one of them :frown:
Oxygen is however, it is always -2.


Fair enough, i understand now,
the question gave me firstlt H2SO4 and so im guessing that i had to find the ox number of sulphur = +6 and so i then had to realise that this ox number stays the same in the equation;
this would give me;
Cu= -(+6-8)
Cu= -(-2)
Cu=+2

Whopeeeeeeeeeeeeeeeee!:smile:

Thanks for all the valuable help:smile:
lanky2610

Oxygen is however, it is always -2.

What about peroxides like H2O2H_2O_2
Reply 6
-1 in Peroxides, -1/2 in Superoxides and -1 when bonded to Fluorine. That's about it.
fait
-1 in Peroxides, -1/2 in Superoxides and -1 when bonded to Fluorine. That's about it.

I know that I was just correcting someone, thanks for caring though :smile:

Latest