Given a chemical reaction, methane (ch4) burns in oxygen (o2) to produce carbon dioxide (co2) and water (h2o). which of these represent an unbalanced equation with the correct chemical formulas? . a.. ch4 + o2 co2 + h2o. b. ch4+ co2 o2 + h2o. c. co2+ h2o ch4+ o2. d. ch4 o2 + co2+ h2o