Oxidation numbers!?

Question

Oxidation numbers!?
Hi i just need someone to write down and explain what the oxidation number is of H2SO4 - how would you work out Hydrogen's number, Sulphurs number and oxygen's number?

Please explain as thoroughly as possible!

Thanks

Harry

Answer 1

look at the periodic table. H is on top group 1, and has a +1 for it's ox. number normally. S and O are in the same family and to make them have an octet they want 2 electrons so they are -2, though S can vary. you probably are trying to find that out.

then it's all about setting up the algebra expression.

H(2)+S+O(4) = -1

1(2)+S+-2(4)=-1

solve and you have your answer

if you're still having problems with this stuff go see your teacher and they'll help

Answer 2

First, of all you need to memorize some common oxidation numbers. Here is a website that lists many of them http://wps.prenhall.com/wps/media/objects/602/616516/Media_Assets/Chapter06/Text_Images/FG06_TB01.JPG

Oxygen is usually assigned an ox number of -2 and hydrogen is uaually assigned an ox number of +1

So for hydrogen gives the species a charge of 2(+1) = +2.
Oxygen gives the species a charge of 4(-2) = -8

The species already has an overall charge of 0. This means the sum of all charge contribution must equal 0.

Therefore 2(+1) + 4(-2) + (Charge S) = 0
Solve for (Charge S)
Charge of S = +6

Finally you can say the oxidation numbers for H2SO4 are:
H = +1, O=-2, S=+6