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Kids sometimes "hit the wall" when they hit the
language and notation required by redox chemistry.
Although we teach this topic at secondary school, I wrote the
following rap song and videotaped intermediate
students performing it in the tradition of their hero, Michael
Jackson. Is it possible that redox is a fun topic? My
students are now convinced it is! Perhaps other teachers would
like to make their own music video! Here are the words:
Refrain
(To the tune of "Rock me Gently" by Neil Diamond)
"Redox gently, redox slowly,
Take it easy, don't you know
We ain't never done redox reactions before!" (x 2)
Rap Beat
Here's what you do, just listen to me.
I'll make it as easy as A, B, C.
Above every element in the whole equation
Write that number called "oxidation".
Assign a zero to elements that are free
Like O2, He, Zn, and C.
Oxygen in compounds is minus two!
(For peroxides only minus one is used.)
Hydrogen in compounds is always plus one!
(For metal hydrides minus one is done.)
In metal compounds the following is true:
Group I, plus one, Group II, plus two.
If the molecule is neutral, then you know,
The sum of the numbers is zero.
If the molecule is an ion without a charge,
The sum of the numbers is zero.
If the molecule is an ion with a charge,
The sum of the numbers is just that large.
So, step number one, as we have said,
Write oxidation numbers above each head!
Refrain (x 2)
Rap Beat
Oxidation-Reduction is the name of the game.
Either one or the other is half of the same.
So each HALF equation is what you will need
On each half of the page before you proceed.
For all elements we first balance mass,
Save oxygen and hydrogen for the last.
Oxygen we balance by adding water,
Then at H+ as you know you "otta".
Now balance charge in each half equation
By adding electrons with the proper notation.
Adjust half-equations by cross-multiplying through
To get equal electrons (any number will do).
Now add the equations, there's not much more to do.
The electrons must cancel if you've carried them through.
Write the final equation as neat as a pin.
Charge and mass must both balance for the fun to begin!
Refrain x 2, fadeout
H+ is read as "H plus". The students who
recorded this video wore dark glasses, baseball caps on
backwards, etc. We got the rap beat from a portable keyboard.
Certainly a new image for redox chemistry!
See Letter re: this article.
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