I can do: NH3 + H2SO4 ---> (NH4)2SO4 I broke it up like this N=1 H=5 SO4=1 on right.. N=2 H=8 SO4=1 I added a coeffiecent of 2 to the NH3..?

on the left. resulting in N=2 H=8 SO4=1 these balance with the number and letters on right. But when using the same method I can't solve for equations like this Cu+HNO3 --> Cu(NO3)2 + H2O + NO2 why cant I solve this using the same method? I've been told this is a 'redox reaction'? is this a... show more on the left. resulting in
N=2
H=8
SO4=1

these balance with the number and letters on right.

But when using the same method I can't solve for equations like this
Cu+HNO3 --> Cu(NO3)2 + H2O + NO2
why cant I solve this using the same method? I've been told this is a 'redox reaction'? is this a different type of one to the one I CAN do?
2 answers 2