View Full Version : Half Equations disconcerning immediate electron transfer
Evil dead
Jan 30, 2007, 11:49 AM
I'm stuck on this:
Cu + HNO3 ------> CuOH + NO2
Here's my attempt:
Copper is oxidised: Cu ---> Cu2+ + 2OH-
Nitric Acid is reduced: HNO3 ---> NO2 + O2-
It looks crap I know..
Evil dead
Jan 30, 2007, 12:21 PM
Here's what I did again:
Cu ---> Cu2+ + 2OH- + 2e-
HNO3 ---> NO2+ + HO-
Any better?
Evil dead
Jan 31, 2007, 02:20 PM
here's my solution:
Cu + HNO3 ---> CuOH + NO2
CU + 2HNO3 ---> Cu(OH)2 + 2NO2
Cu ---> Cu2+ + 2e- : Oxidation
2OH- + 2e- ---> (OH)2 : Reduction
But what happens to the NO3/NO2? Do I have to include that in the half equation? If so, how do I do it?:confused:
Evil dead
Feb 21, 2007, 09:28 AM
Cu: current oxidation state of 0. However as an ion it has an ox-state of +2
HNO3: current oxidation state of 0 (H:+1, NO3:-1).
The reaction goes as planned: Acid + Metal ----> Metal Salt + Hydrogen Gas.
Hydrogen gas = H2, so the equation is not balanced.
Chemical equation now = Cu (s) + 2HNO3 (aq) ----> CuNO3 (aq) + H2 (g)
Therefore the ionic equation must be:
Cu2+2 + 2NO3-2 -----> CuNO3
I ANSWERED MY QUESTION MOTHERFAC*ERS!!
Capuchin
Feb 21, 2007, 09:56 AM
Hey evil dead sorry I didn't answer, I haven't done half equations for many years :)
Evil dead
Feb 21, 2007, 10:00 AM
Lol no problem. I want to become a Chemical Engineer or some sort of Physicist, so I had to make sure this question be answered.