1. This presentation provides the chemistry student with several example problems to become more proficient at working with chemical equations and chemical reactions. Click on the following hyperlinks for practice. Balancing Chemical Equations Naming Chemical Reactions Predicting Chemical Reactions

2. Balancing chemical equations is an important step towards accurately predicting the outcome of a chemical reaction. Let’s start by reviewing some of the basic parts of a chemical equation. Na + Cl  NaCl Write the chemical equation above on your worksheet. Draw a circle around the reactants, then a box around the product. Press the space bar to check you work. Continue

3. Recall that a balanced chemical equation has the same number and type of atoms on the reactant side of the equation as on the product side. For example: H 2 + O 2  H 2 O Na + Cl  NaCl There is one sodium and one chlorine atom on the product side, and the same on the reactant side. If the chemical equation isn’t in balance then we can balance it by multiplying either the products or reactants by a whole number “coefficient”. Write down the following chemical equation in you worksheet and balance it. Press the space bar to check your work.Continue 2H 2 + O 2  2H 2 O

4. Write the following chemical equations on your worksheet and practice balancing them. N 2 + H 2  NH 3 N 2 H 4 +O 2  N 2 + H 2 O Na + N 2  Na 3 N Ca + H 2 O  CaOH + H 2 Press the space bar to check your solutions one at a time. N 2 + 3H 2  2NH 3 N 2 H 4 +O 2  N 2 + 2H 2 O 6Na + N 2  2Na 3 N 2Ca + 2H 2 O  2CaOH + H 2 Continue

5. If you didn’t balance all of the previous chemical equations correctly, be sure to look in you book for more examples and continue to practice. Now let’s work ahead to another important skill in working in chemistry: Classifying Chemical Reactions. There are six main classifications chemists assign to different chemical reactions they are: - Exothermic- Endothermic - Combination- Decomposition - Single Replacement- Double Replacement Take of few minutes to read your assigned classification type in section 10.3 before moving on with this presentation. Continue

6. The next 6 slides contain six different chemical equations. Write the chemical reactions on your worksheet and identify them as exothermic, endothermic, combination, decomposition, single replacement, or double replacement. F + MgCl 2  MgF + Cl 2 Press the space bar to check you answer. Continue Single Replacement

7. KCO 3 + energy  KO + CO 2 Write the chemical reaction on your worksheet and identify it as exothermic, endothermic, combination, decomposition, single replacement, or double replacement Press the space bar to check you answer. Continue Endothermic

8. Ag(NO 3 ) + Cu(SO 4 )  Ag(SO 4 ) + Cu(NO 3 ) Continue Press the space bar to check you answer. Write the chemical reaction on your worksheet and identify it as exothermic, endothermic, combination, decomposition, single replacement, or double replacement Double Replacement

9. NaCl  Na +Cl Continue Press the space bar to check you answer. Write the chemical reaction on your worksheet and identify it as exothermic, endothermic, combination, decomposition, single replacement, or double replacement Decomposition

10. CH 4 + O 2  CO 2 + H 2 O + energy Continue Press the space bar to check you answer. Write the chemical reaction on your worksheet and identify it as exothermic, endothermic, combination, decomposition, single replacement, or double replacement Exothermic

11. H 2 + O 2  H 2 O Continue Press the space bar to check you answer. Write the chemical reaction on your worksheet and identify it as exothermic, endothermic, combination, decomposition, single replacement, or double replacement Combination

12. Let’s now consider the power of a balanced chemical equation. 2H 2 + O 2  2H 2 O The coefficients in front of each term tell a short and simple story about the amount of reactants needed to mix together in order to get an amount of product out. The link between the balanced chemical equation and the amount of matter need to mix or that is produced is the MOLE = 6.022 x 10 23 things In the above chemical reaction – 2 moles of Dihydrogen are mixed with 1 mole of Dioxide to produce 2 moles of Dihydrogenmonoxide (water.) Yahoo! Continue

13. Write the following chemical equation on your worksheet and balance it. CH 4 + O 2  CO 2 + H 2 O How many moles of the reactant, O 2 are needed to produce 1 mole of CO 2 ? How many moles of H 2 O are produced when 2 moles of CH 4 are placed into the reaction? Press the space bar to check you answer. 2 moles O 2 are needed to produce 1 mole of CO 2. 4 moles of H2O are produced. Continue

14. You have finished this presentation of chemical equations and reactions. Now Turn to section 10.3 review in your text and answer questions 1 through 4.