Agenda Ion Quiz #6 Finish up lab Turn in lab and chemical formula sheet Notes on formula weight Practice

Chapter 6 Chemical Quantities 6.3 Molar Mass Copyright © 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings

Molar Mass The molar mass Is the mass of one mol of an element or compound. Is the atomic mass expressed in grams. Copyright © 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings

Molar Mass from the Periodic Table Is the atomic mass expressed in grams. Copyright © 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings

Learning Check Give the molar mass for: A. 1 mol K atoms = ________ B. 1 mol Sn atoms = ________

Solution Give the molar mass for: A. 1 mol K atoms = 39.10 g B. 1 mol Sn atoms = 118.7 g

Molar Mass of a Compound The molar mass of a compound is the sum of the molar masses of the elements in the formula. Example: Calculate the molar mass of CaCl2. Element Number of Moles Atomic Mass Total Mass Ca 1 40.08 g/mol 40.08 g Cl 2 35.45 g/mol 70.90 g CaCl2 110.98 g

Molar Mass of K3PO4 Calculate the molar mass of K3PO4. Element Number of Moles Atomic Mass Total Mass in K3PO4 K 3 39.10 g/mol 117.3 g P 1 30.97 g/mol 30.97 g O 4 16.00 g/mol 64.00 g K3PO4 212.3 g

Some One-Mol Quantities 32.07 g 55.85 g 58.44 g 294.20 g 342.30 g Copyright © 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings

Learning Check What is the molar mass of each of the following? A. K2O B. Al(OH)3

Solution A. K2O 94.20 g/mol 2 mol K (39.10 g/mol) + 1 mol O (16.00 g/mol) 78.20 g + 16.00 g = 94.20 g B. Al(OH)3 78.00 g/mol 1 mol Al (26.98 g/mol) + 3 mol O (16.00 g/mol) + 3 mol H (1.008 g/mol) 26.98 g + 48.00 g + 3.024 g = 78.00 g

Learning Check Prozac, C17H18F3NO, is an antidepressant that inhibits the uptake of serotonin by the brain. What is the molar mass of Prozac? 1) 40.06 g/mol 2) 262.0 g/mol 3) 309.4 g/mol

Solution 3) 309.3 g/mol 17C (12.01) + 18H (1.008) + 3F (19.00) Prozac, C17H18F3NO, is an antidepressant that inhibits the uptake of serotonin by the brain. What is the molar mass of Prozac? 3) 309.3 g/mol 17C (12.01) + 18H (1.008) + 3F (19.00) + 1N (14.01) + 1 O (16.00) = 204.2 +18.14 + 57.00 + 14.01 + 16.00 = 309.4 g/mol