how to balance this equation?

Question

(NH4)2Cr2O7 ---- Cr2O3 + N2 + H2O

plz tell step by step.i m a beginner

Answer 1

This a redox equation but the loss and gain of electrons is balanced. All we need to do is check the H and O.
There are 7 O atoms on the left. We have 3 in Cr2O3, we need 4 more so place a 4 as a coefficient for H2O. That should balance it. Check it atom by atom.