The Student Room Group

help!!! oxidation numbers!!

a)2H2S + 3Br2 --> 4HBr + S2Br2

show changes in oxidation number for two elements stating their original and final oxidation numbers.

i was thinking that S goes from 2- --> +1
and that Br goes from 0 --> -1

b) the ratio initally is 2 to 3 show how your answer in a) agree with this ratio :confused: any thoughts??

Reply 1

The ratio of what? Or is that all it says.
And those oxidation numbers seem right to me.

Reply 2

it says "the equaiton shows that 2 moles of hydrogen sulphide molecules react with 3 moles of bromine molecules. show how your answer in a) agree with this ratio"

Reply 3

Well, then, you've already done it, haven't you? Because the equation shows 2 moles of hydrogen sulphide molecules reacting with 3 moles of bromine molecules.

Reply 4

but the quesiton is asking you to link the oxidation numbers to the ratio. We alredy knew the reaction was 2 to 3 but how does this link to the change in oxidation numbers

Reply 5

-2 --> +1 +3 change
0 ---> -1 -1 change 3:1 ratio but this is wrong this is why im confused