Where do you go to school, and how dumb are your professors? It took me like 2 seconds to balance that equation.

quote:

Originally posted by kewlness you can call it any variable you want... a,b,c,d,e,f,g,h,i,x1,x2,z3,z435 I just chose x1,x2,x3,etc... b/c that's what i usually use in linear algebra btw.. it's x(subscript 1),etc...

hes on the right track

a*Cu + b*HNO3 -- c*Cu(NO3)2 + d*NO + e*H2O

then

a=c (Cu balance)
b=2e (H balance)
b=2c + d (N balance)
3b=6c + d + e (O balance)

matrix
1 0 -1 0 0 0
0 1 0 0 -2 0
0 1 -2 -1 0 0
0 3 -6 -1 -1 0

rref
1 0 0 0 -3/4 0
0 1 0 0 -2 0
0 0 1 0 -3/4 0
0 0 0 1 -1/2 0

letting e=4 clears fractions and
a = 3/4*4 = 3
b = 2*4 = 8
c = 3/4*4 = 3
d = 1/2*4 = 2
e = 4

put back in equation

your prof sucks

quote:

Originally posted by UWM Where do you go to school, and how dumb are your professors? It took me like 2 seconds to balance that equation.

Yeah, after I posted the answer...duuuuuh!

It was a little tricky. You are talking about the first one right??? Cause it was tough!

quote:

Originally posted by Evan Almae Yeah, after I posted the answer...duuuuuh! It was a little tricky. You are talking about the first one right??? Cause it was tough!

The first one was not difficult

I suppose having 4 years of chem/biochem/pchem/achem/etc .. helps though

This redox reaction doesn't look very difficult to balance yet I haven't had any contact with chemistry since high schoool... and that was years ago. I wouldn't solve it now although I was good back in the days

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