Chemical Quantities III A.K.A. Stoichiometry
stoicheion (element; Greek) + metron (measure; Greek) Quantitative relationship between reactants and products Created by Jeremias Benjamin Richter in 1792 What is Stoichiometry?
How much water is produced when 1.5 g of C 6 H 12 O 6 is burned in oxygen? C 6 H 12 O 6 + O 2 CO 2 + H 2 O; Is it balanced? C 6 H 12 O O 2 6 CO H 2 O How do we calculate the mass of a product if we know the mass of a reactant?
We have 1.5 grams of C 6 H 12 O 6 ; we need a mass-mass conversion pathway Create a Conversion Pathway Step 1 Mass of C 6 H 12 O 6 Moles of C 6 H 12 O 6 Step 2Step 3 Moles of H 2 O Mass of H 2 O
Mass of C 6 H 12 O 6 Molar MassMoles of C 6 H 12 O g C 6 H 12 O 6 1 mol C 6 H 12 O 6 = mol C 6 H 12 O g C 6 H 12 O 6 C 6 H 12 O O 2 6 CO H 2 O Step 1 Moles of C 6 H 12 O 6 Molar RatioMoles of H 2 O mol C 6 H 12 O 6 6 mol H 2 O 6 = mol H 2 O 1 mol C 6 H 12 O 6 Moles of H 2 OMolar MassGrams of H 2 O mol H 2 O18 g H 2 O= g H 2 O 1 mol H 2 O Step 2 Step 3
How much aluminum oxide is generated with 2.3 g Al reacting with iron (III) oxide Al + Fe 2 O 3 Fe + Al 2 O 3; is it balanced? 2 Al + Fe 2 O 3 2 Fe + Al 2 O 3 Another Mass-Mass Conversion
Mass of AlMolar MassMoles of Al 2.3g Al1 mol Al= mol Al 27 g Al 2 Al + Fe 2 O 3 2 Fe + Al 2 O 3 Step 1 Moles of AlMolar RatioMoles of Al 2 O mol Al1 mol Al 2 O 3 = mol Al 2 O 3 2 mol Al Moles of Al 2 O 3 Molar MassMass of Al 2 O mol Al 2 O g Al 2 O 3 = 4.3 g Al 2 O 3 1 mol Al 2 O 3 Step 2 Step 3
Mass-Mass Conversions SmartBoard Exercise
Chemical Quantities III Worksheet Complete the first problem as a team in your row Complete the second problem as a pair with the person on your right Complete the next few problems solo It’s your turn to Team, Pair, Solo
Read pp Answer problems pg. 262: 31, 33, 35, 39, 40 Homework