Place coefficients in the reactants and or products to balance the following chemical reactions. 1. fe + s fes 2. h2 + cl2 hcl 3. mg + o2 mgo 4. o2 + h2 h2o 5. hgo hg + o2 6. ca + h2o ca(oh)2 + h2 7. ch4 + o2 co2 + h2o 8. na2o2 + h2(so4) na2(so4) + h2o2 9. n2 + h2 nh3 10. al + o2 al2o3 11. kmno4 k2o + mno + o2