Redox (1 Viewer)

[(^o^)]

Help- Chemistry - Oxidation and Reduction

Can someone explain to me about redox?
It's our "holiday chemistry homework" but I don't get redox at all!
Espeically these 2 below, the questions are asking to find the reducing agent and the oxidising agent.

Cl2 (g) + 2Br- (aq) --> Br2 (l) + 2Cl- (aq)

2I- (aq) + Br2 (l) --> 2Br- (aq) + I2 (s)

I've got the answers from the CD-rom we are being given, but I still can't figure out how to do it by looking at the answers. Please give me a hand, thanks.

 

[sam04u]

remember OIL RIG
Oxidation I:Is L:loss
R:Reduction I:Is G:Gain
(i could answer it for you but here is more then enough for you to figure it out if you still dont get it il explain it in detail shouldnt be do difficult)

 

[sam04u]

look at Ions to figure out where loss is also

 

[mei_ling03]

reduction-oxidation reactions are just a transfer of electrons. it involves changes to the oxidation number. (oxidation number is basically valence number)
Cl2 (g) + 2Br- (aq) --> Br2 (l) + 2Cl- (aq)
you see in the first example that the Cl2 has an oxidation number of 0. when 2 electrons are taken from the Cl2, you see that the oxidation number rises to 1 to form 2Cl-. hences, this is an oxidation reaction (Oxidation Is Gain). Cl2 --> 2Cl- + 2e-
the 2Br- begins with an oxidation number of 1. by adding 2 electrons, this oxidation number is REDUCED to 0 when it becomes Br2. (Reduction Is Loss). 2Br- + 2e- --> Br2

make sense?

 

[(^o^)]

Yay thanks for helping!
OIL RIG haha yup i'll remember that from now on =D

 

[*girl04*]

damn it, we might have to do that soon in chem... grrrrr

 

[Xayma]

Originally posted by *girl04*
damn it, we might have to do that soon in chem... grrrrr

Dont worry redox is just a simple version of changes in oxidation states, which you will do next year.

Just got to remember that it is the transfer of electrons and look at the change in valencies.

 

[(^o^)]

Originally posted by *girl04*
damn it, we might have to do that soon in chem... grrrrr

haha don't worry it's easy once you get it.
Our school hasn't taught us redox yet but the teacher asked us to do it as "holiday homework" so yeh. =)

 

[sam04u]

Originally posted by mei_ling03
reduction-oxidation reactions are just a transfer of electrons. it involves changes to the oxidation number. (oxidation number is basically valence number)
Cl2 (g) + 2Br- (aq) --> Br2 (l) + 2Cl- (aq)
you see in the first example that the Cl2 has an oxidation number of 0. when 2 electrons are taken from the Cl2, you see that the oxidation number rises to 1 to form 2Cl-. hences, this is an oxidation reaction (Oxidation Is Gain). Cl2 --> 2Cl- + 2e-
the 2Br- begins with an oxidation number of 1. by adding 2 electrons, this oxidation number is REDUCED to 0 when it becomes Br2. (Reduction Is Loss). 2Br- + 2e- --> Br2

make sense?

Sorry mate youve got it the wrong way round...(or mayve your just trying to be tricky and confuse him.. ah its just me always paranoid when im UTI

 

[mei_ling03]

Originally posted by sam04u
Sorry mate youve got it the wrong way round...(or mayve your just trying to be tricky and confuse him.. ah its just me always paranoid when im UTI

yeah? i may very well be wrong..but an explanation to back that up might be nice

 

[JamiL]

i dont get that... wtf is that we r not doin that yet

 

[(^o^)]

Originally posted by mei_ling03
yeah? i may very well be wrong..but an explanation to back that up might be nice

As what sam04u says..
it should be OIL RIG right?
Oxidation is loss
Reduction is gain
LOL this way is so good, now I remember which is which!

Originally posted by
JamiLi dont get that... wtf is that we r not doin that yet

Well... I'm sure you'll learn it soon =)
I think our class is just rushing the whole "metal" chapter because we are having a test on metals

 

[mei_ling03]

Originally posted by (^o^)
As what sam04u says..
it should be OIL RIG right?
Oxidation is loss
Reduction is gain
LOL this way is so good, now I remember which is which!

hahaha lol.. MY APOLOGIES!.. i wrote the acronym wrong - now i get what the sam04u was on about!
OIL RIG
oxidation is the LOSS of electrons but the ADDITION in oxidation number
reduction is the GAIN in electrons but the REDUCTION in oxidation number

lol sorry sam04u!

 

[nick1048]

the one that loses is the reducing agent and the one that gains is the oxidation. However the oxidised product is called the reductant and the reduced product is called the oxident... Tricky, but u'll get used to it...

 

[Misturi]

ARGH chem...

umm yeah remember OIL RIG. You'll be fine.