How do you balance Cr + Fe(NO_3)_2 -> Fe + Cr(NO_3)_3Cr+Fe(NO3)2Fe+Cr(NO3)3?

1 Answer
Dec 28, 2016

2Cr+3Fe(NO_3)_2 rarr 3Fe + 2Cr(NO_3)_32Cr+3Fe(NO3)23Fe+2Cr(NO3)3

Explanation:

We write the oxidation rxn:

CrrarrCr^(3+) + 3e^-CrCr3++3e (i)(i)

And then the reduction rxn:

Fe^(2+) +2e^(-) rarr FeFe2++2eFe (ii)(ii)

And then cross mulitply, 2xx(i) +3xx(ii)2×(i)+3×(ii)

2Cr+3Fe(NO_3)_2 rarr 3Fe + 2Cr(NO_3)_32Cr+3Fe(NO3)23Fe+2Cr(NO3)3

Is mass balanced? Is charge balanced?