Question

Which of the following chemical reactions is not an oxidation-reduction reaction?

Answer 1

for some reason, i got the first one wrong on my test...

Answer 2

@dan815
@zepdrix
@thomaster
@undeadknight26
@surjithayer
@mathmate
@Jadeishere
@Jaynator495
@superhelp101
@TheRaggedyDoctor
@amoodarya
@aryandecoolest
@sweetburger

Answer 3

I think it's A, but idk how to explain why

Answer 4

@Jadeishere i thought so too but idk why they marked it wrong! ):

Answer 5

I would say C. Is it correct?

Answer 6

So oxi-red reactions charge from one side to the other, and A does do that with Ba... Wow, now I know why it's wrong

Answer 7

The best way to answer this kind of (defition related) questions is to understand what the definition means, and learn about it.
Here is a link that will give you the answer (and more):

http://www.shodor.org/unchem/advanced/redox/

Answer 8

@Jadeishere @Hoslos so we agree on C?

Answer 9

Let me explain.
Oxidation-Reduction reactions are the one in which from reactants to products side, there has been loss and gain of electron in at least 2 different elements.
NB: The oxidation number of an element in its standard state is 0.
C answers it because at the reactants side, Zn has oxidation number 0 and on the products side, has oxidation number +2.
On the other hand, the Zn could have lowered its oxidation number on the products side, given that the oxidation number of S can also change, affecting the Zn's.
Hydrogen in the reactants side had oxidation number +1 and in the products side, 0.
Meaning, it reduced. Zn also appeared to reduce.
At the end of the day, we cannot find the element which oxidized, hence it is not an oxidation-reduction reaction.

Answer 10

it was actually wrong )): @Hoslos

Answer 11

Then the answer must be A.
Because in both B and D, the reactants had 0 oxidation numbers and in the products side, one of them increased and the other reduced, making them reduction - oxidation reactions.