njetcheverry njetcheverry 04-03-2021 Chemistry contestada Balanced or Unbalanced? Write a “B” for Balanced and a “U” for Unbalanced. ______ 11.CH4 + O2 à CO2 + 2 H2O ______ 12. NaBr + CaF2 à NaF + CaBr2 ______ 13. 4 Fe + 3 O2 à 2 Fe2 O3