Table of Contents Chapter 12 Stoichiometry 12 1

Table of Contents Chapter 12: Stoichiometry 12. 1: What is Stoichiometry? 12. 2: Stoichiometric Calculations

Table of Contents Chapter 12: Stoichiometry • Stoichiometry is the mathematical study of chemical reactions. 12. 1: Mole-Mass • Stoichiometry ratios • The molar ratio of one reactant/product to 12. 2: Stoichiometric Calculations another reactant/product

Table of Contents Chapter 12: Stoichiometry • Stoichiometry ratios • Used calculate how much reactant (or 12. 1: to. Mole-Mass product) will be consumed (or created) in a chemical reaction. 12. 2: Stoichiometric Calculations • It shows quantitative relationship between the reactants and products.

Stoichiometry: Basic Concepts Stoichiometry • The coefficients represent… 2 H 2 + O 2 → 2 H 2 O (Ionic compounds = formula units) 2 H 2 molecules + 1 O 2 molecule → 2 H 2 O molecules 2 moles H 2 + 1 mole O 2 → 2 moles H 2 O ratio: 2 mol H 2 : 1 mol O 2

Stoichiometry: Basic Concepts Stoichiometry problems 1. Write balanced equation a. Identify reactants and products b. Write their chemical formulas (balance charges) c. Balance the equation

Stoichiometry: Basic Concepts Stoichiometry problems 2. Convert to moles Just like we’ve been practicing 3. Convert from moles known to moles of unknown (from balanced equation) 4. Convert moles to needed units

Stoichiometry: Mass-Mass equations Ex 1) How many grams copper II chloride can be produced by reacting 10. 25 grams of sodium chloride with excess copper II nitrate? (Double Displacement Reaction) 2 Na. Cl + Cu(NO 3)2 Cu. Cl 2 + 2 Na. NO 3 11. 8 10. 25 g Na. Cl 1 mol Cu. Cl 2 134. 5 g Cu. Cl 2 = 58. 5 g Na. Cl 2 mol Na. Cl 1 mol Cu. Cl 2

Stoichiometry: Mass-Mass equations Ex 2) How many grams oxygen will be consumed when 12. 5 grams of methane (CH 4) are consumed in a combustion reaction? (Combustion) CH 4 + 2 O 2 CO 2 + 2 H 2 O 49. 9 12. 5 g CH 4 1 mol CH 4 2 mol O 2 32. 0 g O 2 = 16. 0 g CH 4 1 mol O 2

Stoichiometry: Mass-Mole equations Ex 3) How many moles copper II chloride can be produced by reacting 10. 25 grams of sodium chloride with excess copper II nitrate? 2 Na. Cl + 0. 0876 mol Cu. Cl 2 Cu(NO 3)2 Cu. Cl 2 + 2 Na. NO 3 = 10. 25 g Na. Cl 1 mol Cu. Cl 2 58. 5 g Na. Cl 2 mol Na. Cl

Stoichiometry: Mole-Mass equations Ex 4) How much carbon dioxide will be produced when 3. 92 moles of oxygen are consumed in a combustion reaction? CH 4 + 2 O 2 CO 2 + 2 H 2 O 86. 2 g CO 2 = 3. 92 mol O 2 1 mol CO 2 44. 0 g CO 2 2 mol O 2 1 mol CO 2

Stoichiometry: Moles–Moles equations Ex 5) How many moles sodium hydroxide can be produced when 3. 12 moles sodium sulfate are reacted with excess potassium hydroxide (double displacement)? Na 2 SO 4 + 2 KOH --> K 2 SO 4 + 2 Na. OH 6. 24 mol Na. OH = 3. 12 mol Na 2 SO 4 2 mol Na. OH 1 mol Na 2 SO 4

Just so you know… • You can now do the entire Web. Assign ch 12 • Check the website for hints! mmecall. weebly. com You can also find… Notes homework hints