100 likes | 118 Views
Learn to convert mass or count to moles, solve mole quantity ratios, and convert back if needed. Practice calculations to determine atom counts and molecule masses. Prepare for higher-level stoichiometry problems.
E N D
Homework 6 posted and due Monday 3/5 Sigh, another Monday…
Moles Level 2: `Body Parts’ Calculations- the Process 1) Convert any mass or count to moles (divide up) 2) Set up appropriate ratio with unknown mol quantity (m) and solve for m. 3) If necessary re-convert m to mass or count (multiply down)
Mole Calculations: part 2 (cont.) 6) moles to atom count how many atoms of O are present in 0.8333 mol of C6 H12O6? =30*1023
7) Moles to atom count: how many atoms of C are in 0.02777 mol of C6H12O6? (1 mol =6*1023) • 1.662*1022 • 1.3*1024 • 1.0*1023 • 1.0*1024
Mole Calculations: part 2 (cont.) 8) mass to molecules: how many atoms of H in C6 H12O6are combined with 84 g of C ? 84 *1023 atoms ofH 8) atoms to mass: how many grams of H are combined with 2.4*1024 atoms of O in C6H12O 6 ? 8 grams H
9) mass molecules: How many molecules of C6H12O6 are present in a sample containing 32 g of O (at. wt=16 g/mol)? 1 1 mol count=6*1023 • 12*1023 • 5*1024 • 3.3*1023 • 2.0*1023
Mole Calculations: part 2 (cont.) 10) atoms to mass: how many grams of H are combined with 2.4*1024 atoms of O in C6H12O 6 ? 8 grams H
How many grams of C are in a sample containing 4.1666*1022 molecules of C6H12O6 . (1 mol count=6*1023) • 0.833 g • 5.000 g • 10.37 g • 17.28 g
The road trip through mole land so far… • Basic mole-mass-count conversions ( divide up, multiply down): =Moles level 1 • Mole ratio conversion within a compound (`body parts’ relationships) = Moles level 2
The mole road ahead... • % composition problems and combustion analysis (pp. 94-103) : moles level 2b • Reaction balancing (pp. 105-108) • Reaction stoichiometry predictions, limiting yields and % yields ( pp. 108-123): moles level 3