1 Chapter 3

2 1 trio= 3 singers 1 six-pack Cola=6 cans Cola drink 1 dozen donuts=12 donuts 1 gross of pencils=144 pencils Collection Terms

3 Contains 6.02 x particles 1 mole C = 6.02 x C atoms 1 mole H 2 O = 6.02 x H 2 O molecules 1 mole NaCl = 6.02 x Na + ions and 6.02 x Cl – ions A Moles of Particles

4 Moles of elements 1 mole Mg = 6.02 x Mg atoms 1 mole Au = 6.02 x Au atoms Moles of compounds 1 mole NH 3 = 6.02 x NH 3 molecules 1 mole C 9 H 8 O 4 = 6.02 x aspirin molecules Examples of Moles

x particles 1 mole or 1 mole 6.02 x particles Avogadro’s Number

The Mole and Molar The mole is defined as the amount of a substance that contains as many elementary entities as there are atoms in exactly 12 g of carbon-12. The experimentally determined number is called Avogadro’s number (N A ) N A = x 10 23

The Mole and Molar Mass One mole each of some familiar substances: sulfur (left) copper (middle) mercury (right) helium (in balloon) N A = x 10 23

8 Suppose we invented a new collection unit called a mep. One mep contains 8 objects. A. How many paper clips in 1 mep? 1) 12) 43) 8 B. How many oranges in 2.0 meps? 1) 42) 83) 16 C. How many meps contain 40 gummy bears? 1) 52) 103) 20 Learning Check

9 Suppose we invented a new collection unit called a mep. One mep contains 8 objects. A. How many paper clips in 1 mep? 3) 8 B. How many oranges in 2.0 meps? 3) 16 C. How many meps contain 40 gummy bears? 1) 5 Solution

10 1. Number of atoms in mole of Al 1) 500 Al atoms 2) 6.02 x Al atoms 3) 3.01 x Al atoms 2.Number of moles of S in 1.8 x S atoms 1) 1.0 mole S atoms 2) 3.0 mole S atoms 3) 1.1 x mole S atoms Learning Check

11 1. Number of atoms in mol of Al 3) 3.01 x Al atoms mol Al x 6.02 x Al atoms 1 mol Al 2. Number of moles of S if a sample of S contains 1.80 x S atoms 2) 3.0 mole S atoms 1.80 x S atoms x 1 mol S 6.02 x S atoms Solution

12 Number of grams in 1 mole Equal to the numerical value of the atomic mass 1 mole of C atoms= 12.0 g 1 mole of Mg atoms =24.3 g 1 mole of Cu atoms =63.5 g Molar Mass

13 Give the molar mass to 0.1 g A. 1 mole of Br atoms =________ B.1 mole of Sn atoms =________ Learning Check

14 Give the molar mass to 0.1 g A. 1 mole of Br atoms =79.9 g/mole B.1 mole of Sn atoms =118.7 g/mole Solution

15 Mass in grams of 1 mole equal numerically to the sum of the atomic masses 1 mole of CaCl 2 = g/mole 1 mole Ca x 40.1 g/mole + 2 moles Cl x 35.5 g/mole 1 mole of N 2 O 4 = 92.0 g/mole 2 moles N x 14.0 g/mole + 4 moles O x 16.0 g/mole Molar Mass of Compounds

16 A. 1 mole of K 2 O = ______g B. 1 mole of antacid Al(OH) 3 = ______g Learning Check

17 A. 1 mole of K 2 O= 94.2 g 2 K x 39.1 g/mole + 1 O x 16.0 g/mole B. 1 mole of antacid Al(OH) 3 = 78.0 g 1 Al x 27.0 g/mole + 3 O x 16.0 g/mole + 3 x 1.0 Solution

18 Prozac, C 17 H 18 F 3 NO, is a widely used antidepressant that inhibits the uptake of serotonin by the brain. It has a molar mass of 1) 40.0 g/mole 2) 262 g/mole 3) 309 g/mole Learning Check

19 Prozac, C 17 H 18 F 3 NO, is a widely used antidepressant that inhibits the uptake of serotonin by the brain. It has a molar mass of 3) 309 g/mole 17C (12.0) + 18H (1.0) + 3F (19.0) + 1N (14.0) + 1 O (16.0) Solution

20 What is the percent carbon in C 5 H 8 NO 4 (MSG monosodium glutamate), a compound used to flavor foods and tenderize meats? 1) 8.22 %C 2) 24.3 %C 3) 41.1 %C Learning Check

21 Molar mass = g/mole % = total g C x 100 total g compound = 60.0 g C x 100 = 41.1% C g MSG Solution

22 Methane CH 4 known as natural gas is used in gas cook tops and gas heaters. Express the molar mass of methane in the form of conversion factors. Molar mass of CH 4 = 16.0 g 16.0 g CH 4 and 1 mole CH 4 1 mole CH g CH 4 Molar Mass Factors

23 Acetic acid CH 3 COOH is the acid in vinegar. It has a molar mass of 60.0 g/mole. 1 mole of acetic acid = ____________ 1 mole acetic acid or g acetic acid g acetic acid 1 mole acetic acid Learning Check

24 Acetic acid CH 3 COOH is the acid in vinegar. It has a molar mass of 60.0 g/mole. 1 mole of acetic acid = 60.0 g acetic acid 1 mole acetic acid or 60.0 g acetic acid 60.0 g acetic acid1 mole acetic acid Solution

25 molar mass Grams Moles Calculations with Molar Mass

26 Aluminum is often used for the structure of light-weight bicycle frames. How many grams of Al are in 3.00 moles of Al? 3.00 moles Al ? g Al Moles and Grams

27 1. Molar mass of Al1 mole Al = 27.0 g Al 2. Conversion factors for Al 27.0g Al or 1 mol Al 1 mol Al 27.0 g Al 3. Setup3.00 moles Al x 27.0 g Al 1 mole Al Answer = 81.0 g Al

28 The artificial sweetener aspartame (Nutri- Sweet) formula C 14 H 18 N 2 O 5 is used to sweeten diet foods, coffee and soft drinks. How many moles of aspartame are present in 225 g of aspartame? Learning Check

29 1. Molar mass of Aspartame C 14 H 18 N 2 O 5 (14 x 12.0) + (18 x 1.01) + (2 x 14.0) + (5 x 16.0) = 294 g/mole 2. Setup 225 g aspartame x 1 mole aspartame 294 g aspartame = mole aspartame Solution