2. Balancing Chemical Equations By: Ryan McMillan, Matt McGovern, and Tarique Martin

3. Writing Chemical Equations  In order to balance any chemical equation, you first must write the correct formulas of each reactant and each product. This must always be the first step, or your equation will be incorrect. Then you have to balance the equation so that it is numerically correct. In each Balanced Equation, both sides of the equation have the same number of atoms of every element. It is important to balance equations because the equation must agree with the law of conservation of mass. Chemical reactions cannot create or destroy atoms, but they are rearranged.

4. Rules for Balancing Equations 1.Figure out the correct formulas for every reactant and product. 2.Write the formulas for all reactants on the left side of the equation, and write the formulas for every product on the right side of the formula. Make sure that there is a yields sign in between the two formulas. If more than one reactant or product is involved, separate their formulas with a plus sign. 3.Count the number of atoms of every element in both the reactants and products. Be sure that if there is a polyatomic ion involved, that you only count it as one unit. 4.Balance the elements by using Coefficients, small whole numbers that are in front of the chemical formulas in any equation. When there is no numerical coefficient in front of the formula, it should be assumed that the coefficient is actually 1. When balancing the equation, NEVER, EVER CHANGE THE SUBSCRIPTS IN THE FORMULA.

5. More Rules for Balancing Equations 5. To insure balance of the equation, check to see that each atom or polyatomic ion is balanced. 6. To finalize, make sure that all of the coefficients are of the lowest possible ratio.

7. Question?!?!?!?!?!  2H 2 + O 2 —› ? A.HOHO B.2H 2 O2H 2 O C.H 2 O 2H 2 O 2 D.4H 4 O 24H 4 O 2

8. Questions!?!?!?!?!?!?!?!?!?  Balance the following equation: Al + N 2 ―› AlN A.2Al + N 2 ―› 2AlN2Al + N 2 ―› 2AlN B.Al 2 + N 2 ―› AlNAl 2 + N 2 ―› AlN C.Al + -2N ―› AlNAl + -2N ―› AlN D.Al 2 + N 3 ―› 2AlNAl 2 + N 3 ―› 2AlN

9. Pictures and diagrams

10. Homework question Balance the following equations: 1.NaCl + H 2 SO 4 —› Na 2 SO 4 + HCl 2.Carbon + Oxygen—› Carbon trioxide 3.Potassium Nitrate —› Potassium Nitrite + Oxygen

11. CHAPTER IS