[slu1986]

What are the coefficients in front of NO3- (aq) and Cu (s) when the following redox equation is balanced in an acidic solution:

                        ____NO3- (aq) + _____ Cu (s) ----> _____ NO (g) + _____ Cu^2+ (aq)

A) 2,3 <-------This is the answer that I got
B) 2,6
C) 3,4
D) 3,6

This is how I worked out the problem:

NO3- (aq) ---> NO (g)                                               Cu (s) -----> Cu^2+ (aq)
NO3- (aq) ---> NO (g) + 2 H2O                                   3e-[Cu (s) -----> Cu^2+ (aq) + 2e-]
NO3- (aq) + 4 H+ ---> NO (g) + 2 H2O                       3Cu (s) ----> 3Cu^2+ (aq) + 6e-
2e-[NO3- (aq) + 4 H+ + 3e- ----> NO (g) + 2 H2O] 
2NO3- (aq) + 8H+ +6e- ------> 2NO (g) + 4 H2O

    2 NO3- (aq) + 3 Cu (s) ----> 2 NO (g) + 3 Cu^2+ (aq)

I was just wondering if I solved the problem right and got the correct answer ?

[Ak]

i got the same answer (2NO3 and 3CU) so im pretty sure you did it right

[Borek]

Oxygen is not balanced, charge is not balanced. This is NO₃^-, not NO^3-. This is in acidic solution, you can use H⁺ and H₂O when balancing oxygen/hydrogen.

[slu1986]

Oxygen is not balanced, charge is not balanced. This is NO₃^-, not NO^3-. This is in acidic solution, you can use H⁺ and H₂O when balancing oxygen/hydrogen.

Yea I balanced the equation with H20 and H+..I just didn't post the whole balanced equation on my post.  I just filled in the coefficients that it was asking for in the problem, but here is the balanced equation that I got...

2NO3- (aq) + 3 Cu (s) + 8H+  -----> 2NO (g) + 3 Cu^2+ (aq) + 4 H2O (l)

the coefficients in front of NO3 - (aq) and Cu (s) when the following redox equation is balanced in an acidic solution are 2 NO3- (aq) and 3 Cu (s).

[Borek]

OK