Question

Cu + HNO3 --> Cu(NO3)2 + NO + H2O how to balance... WILL GIVE 15 POINTS

Answer 1

Answer:

3 Cu + 8 HNO3 --> 3 Cu(NO3)2 + 2 NO + 4 H2O

Explanation:

Make sure both sides are equal

3 Cu + 8 HNO3 --> 3 Cu(NO3)2 + 2 NO + 4 H2O

// start by those elements that change their oxidation degree

Cu and N

// also you can write reduction-oxidation reactions

$Cu^{0}$ + 2 $e^{-}$ --> $Cu^{-2}$ | 2

$N^{+5}$ - 3 $e^{-}$ -->  $N^{+2}$ | 3

// write the numbers of electrons that are lost/gained as the coefficients of the opposite elements

// then check if H and O are the same on both sides

// adjust if they aren't.

Answer 2

Answer:

Explanation:

3Cu + 2HNO3 --> 3Cu(NO3)2 + 2NO + 2H2O