What is Stoichiometry Objectives 6 0 Solve stoichiometric

What is Stoichiometry? Objectives: 6. 0 Solve stoichiometric problems involving relationships among the number of particles, moles, and masses of reactants and products in a chemical reaction 6. 3 Identifying the nomenclature of ionic compounds, binary compounds, and acids 6. 4 Classifying chemical reactions as composition, decomposition, single replacement, or double replacement Other AOD C. 6. 1 Define stoichiometry, reactants, and products. Other AOD C. 6. 2 Explain the law of conservation of mass. Other AOD C. 6. 3 Explain the concept of mole in terms of Avogadro's number.

Stoichiometry • Def. : the quantitative study of relationships between amounts of reactants used and products formed in a chemical reaction • Let’s think for a moment. If I hand you a dozen chocolate chips, can you make a dozen chocolate chip cookies? • Well, every chemical equation is just a recipe!

Let’s Review! • Iron + oxygen react to produce iron (III) oxide. 1. Write AND BALANCE the chemical equation. ANSWER: 4 Fe(s) + 3 O 2(g)→ 2 Fe 2 O 3(s) 2. What type of reaction is this? 3. How many moles of each compound are represented? 4. How many grams of each compound are represented?

Review, continued…. . • Aluminum + bromine react to produce aluminum bromide 1. Write AND BALANCE the chemical equation. ANSWER: 2 Al(s) + 3 Br 2(l)→ 2 Al. Br 3(s) 2. What type of reaction is this? 3. How many moles of each compound are represented? 4. How many grams of each compound are represented?

Review – 1 More! • Propane (C 3 H 8) and oxygen react to produce carbon dioxide and water. 1. Write AND BALANCE the chemical equation. ANSWER: C 3 H 8(g) + 5 O 2(g)→ 3 CO 2(g) + 4 H 2 O 2. What type of reaction is this? 3. How many moles of each compound are represented? 4. How many grams of each compound are represented?

Law of Conservation of Mass • In every example, mass was conserved, meaning the mass of the reactants EQUALS the mass of the products! • While mass was equal on both sides of the equations, what was different? ANSWER: number of molecules or number of moles

Assignment • Let’s look at Example Problem 12 -1 on p. 355. (This is the last equation we balanced. ) • Notice how they write the equation “in terms of” molecules, moles, and mass. • Now do the Practice Problems on p. 356 --- ONLY demonstrating conservation of mass, not the rest of the directions.

Mole Ratios • Def. : the ratio of the number of moles of any two substances in a balanced chemical equation. • Let’s look back at the 3 equations we balanced. • In the first one, we can identify several mole ratios: – 4 Fe/3 O 2 – 4 Fe/2 Fe 2 O 3 – 3 O 2/2 Fe 2 O 3 OR OR OR 3 O 2/4 Fe 2 Fe 2 O 3/3 O 2

Mole Ratios, continued…. . • • What are the possible mole ratios for the other two example problems we worked? Assignment: 1. Practice Problems (p. 357) 2. Study Guide for Content Mastery: pp. 67 -68