1. Chemical Equations And balancing equations

2. Chemical Equation CH 4 + O 2  CO 2 + H 2 O Reactantsproducts  Means to produce

3. Balancing Chemical Equations In a chemical reaction, atoms are neither created nor destroyed. All atoms present in the reactants must be accounted for among the products. To accomplish this rule you must balance the equation

4. Balancing Chemical Equations The accepted convention is that the “best” balanced equation is the one with the smallest whole numbers. These whole numbers are called the coefficients for the balanced equation.

5. Unbalanced Equations 1. HgO  Hg + O 2 1 Hg and 1 O  1 Hg and 2 O 2. C + O 2  CO 2 ▫1 C and 2 O  1 C and 2 O 3. Zn + HCl  H 2 + ZnCl 2  1 Zn and 1 H and 1 Cl  2 H and 1 Zn and 2 Cl

6. Answers for Balanced Equations 1. 2HgO  2Hg + O 2 2. C + O 2  CO 2 3. Zn + 2HCl  H 2 + ZnCl 2

7. More Practice at Balancing Equations KBr + H 3 PO 4  K 3 PO 4 + HBr NH3 + Cl2  NH4Cl + NCl3 CaC2 + H2O  Ca(OH)2 + C2H2

8. Answers 3KBr + H 3 PO 4  K 3 PO 4 + 3HBr 4NH3 + 3 Cl2  3 NH4Cl + NCl3 CaC2 + 2 H2O  Ca(OH)2 + C2H2