1. 1 Chapter 7 Chemical Quantities 7.2 Molar Mass Basic Chemistry Copyright © 2011 Pearson Education, Inc. Lithium carbonate produces a red color in fireworks.

2. 2 Molar Mass The molar mass is the mass of one mol of an element or compound is the atomic mass expressed in grams Basic Chemistry Copyright © 2011 Pearson Education, Inc.

3. 3 Molar Mass from the Periodic Table Basic Chemistry Copyright © 2011 Pearson Education, Inc.

4. 4 Give the molar mass for A. 1 mol of K atoms =________ B. 1 mol of Sn atoms =________ Learning Check Basic Chemistry Copyright © 2011 Pearson Education, Inc.

5. 5 Give the molar mass for A. 1 mol of K atoms =39.10 g B.1 mol of Sn atoms =118.7 g Solution Basic Chemistry Copyright © 2011 Pearson Education, Inc.

6. Guide to Calculating Molar mass 6 Basic Chemistry Copyright © 2011 Pearson Education, Inc.

7. 7 Molar Mass of a Compound For a compound, the molar mass is the sum of the molar masses of the elements in the formula. Example: Calculate the molar mass of CaCl 2. ElementNumber of Moles Atomic MassTotal Mass Ca140.08 g/mol 40.08 g Cl235.45 g/mol 70.90 g CaCl 2 110.98 g Basic Chemistry Copyright © 2011 Pearson Education, Inc.

8. 8 Molar Mass of K 3 PO 4 Determine the molar mass of K 3 PO 4. ElementNumber of Moles Atomic MassTotal Mass in K 3 PO 4 K339.10 g/mol 117.3 g P130.97 g/mol 30.97 g O416.00 g/mol 64.00 g K 3 PO 4 212.3 g Basic Chemistry Copyright © 2011 Pearson Education, Inc.

9. 9 Some One-Mol Quantities Basic Chemistry Copyright © 2011 Pearson Education, Inc.

10. 10 Calculate the molar mass for Al(OH) 3 with four significant figures. 1) 44.00 g/mol 2) 75.00 g/mol 3) 78.00 g/mol Learning Check Basic Chemistry Copyright © 2011 Pearson Education, Inc.

11. 11 STEP 1 Obtain the molar mass of each element. Al 26.98 g/mol O 16.00 g/mol H 1.008 g/mol STEP 2 Multiply each by the subscript. 1 mol Al x 26.98 g Al = 26.98 g 1 mol Al 3 mol O x 16.00 g O = 48.00 g 1 mol O 3 mol H x 1.008 g H = 3.024 g 1 mol H STEP 3 Calculate the molar mass by adding the masses of the elements. 1 mol of Al(OH) 3 = 78.00 g (3) Solution Basic Chemistry Copyright © 2011 Pearson Education, Inc.

12. 12 Prozac, C 17 H 18 F 3 NO, 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 Learning Check Basic Chemistry Copyright © 2011 Pearson Education, Inc.

13. 13 Prozac, C 17 H 18 F 3 NO, is an antidepressant that inhibits the uptake of serotonin by the brain. What is the molar mass of Prozac? STEP 1 Obtain the molar mass of each element. C 12.01 g/mol H 1.008 g/mol F 19.00 g/mol N 14.01 g/mol O 16.00 g/mol STEP 2 Multiply each by the subscript in the formula. 17 mol C x 12.01 g C = 204.2 g 1 mol C 18 mol H x 1.008 g H = 18.14 g 1 mol H Solution Basic Chemistry Copyright © 2011 Pearson Education, Inc.

14. Solution (continued) STEP 2 3 mol F x 19.00 g F = 57.00 g 1 mol F 1 mol N x 14.01 g N = 14.01 g 1 mol N 1 mol O x 16.00 g O = 16.00 g 1 mol O STEP 3 1 mol of C 17 H 18 F 3 NO = 309.4 g 14