Worksheet: Balancing Equations I. KEY Name __________________ Fill in the blanks with the most appropriate term: chemical equation A ________________ ________________ tells the story of a chemical Reactants reaction. ________________ are the starting substances in the reaction products while ________________ are the new substances that are formed. The large numbers in front of some of the formulas are called coefficients balance ________________. These numbers are used to ________________ the equation because chemical reactions must obey the Law of Conservation ________________ of Matter. The number of atoms of each element on equal both sides of the equation must be ________________ because matter created destroyed cannot be ________________ or ________________. When balancing coefficients equations, the only numbers that can be changed are ________________; formulas / subscripts remember that ________________ must never be changed in order to balance an equation. II. Balance the following equations: 1. 4Al + 3 O2 2. C3H8 3. Al(NO3)3 + 5 O2 + 2Al2O3 3CO2 3NaOH + 4H2O Al(OH)3 + CHEMISTRY: A Study of Matter © 2004, GPB 6.24a 3NaNO3 4. 2KNO3 5. 3 O2 6. 2KClO3 7. 3BaF2 8. H2SO4 9. 2Al 10. WO3 + + + 2KNO2 CS2 + + CO2 2KCl + 2K3PO4 + O2 + 3 O2 Ba3(PO4)2 Mg(NO3)2 3H2SO4 3H2 2SO2 + MgSO4 + Al2(SO4)3 + W 6KF + 3H2O CHEMISTRY: A Study of Matter © 2004, GPB 6.24b 2HNO3 3H2