1 Chapter The Mole 5.6 Molar Mass 5.7 Mole Relationships in Chemical Equations 5.8 Mass Calculations for Reactions

Do Now … What is the molar mass of H 2 0? Calculate how many grams of H20 are in 1 moles of H 2 0. Calculate how many grams are in 5 moles of H pts 2

Objective I will be able to calculate the amount of product in a chemical equation 4 ouf of 5 times and demonstrate my knowledge of “Conservation of Mass”. 3

Agenda… Do now 10 min Lecture 30 min Handout 30 min Reading 30 min Achieve min 4

5 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

6 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

7 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

9 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

10 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

11 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

12 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 4.50 x S atoms 2) 3.0 mole S atoms 4.50 x S atoms x 1 mol S 6.02 x S atoms Solution

13 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

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

15 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

16 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 = 74.0 g/mole 2 moles N x 14.0 g/mole + 4 moles O x 16.0 g/mole Molar Mass of Compounds

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

18 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

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 1) 40.0 g/mole 2) 262 g/mole 3) 309 g/mole Learning Check

20 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

21 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

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

23 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

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 = ____________ 1 mole acetic acid or g acetic acid g acetic acid 1 mole acetic acid Learning Check

25 Calculating Mass of A Substance Balance equation Convert starting amount to moles Use coefficients to write a mol-mol factor Convert moles of desired to grams

26 Points to Remember 1. Read an equation in moles 2. Convert given amount to moles 3. Use mole factor to give desired moles 4. Convert moles to grams grams (givengrams (desired) moles (given)moles (desired)

How to convert Moles to grams First set up the equation to see what your starting with and want to end with. Example: How many grams of oxygen are in 2.0 moles of O 2 ? Set up: 2.0 moles O 2 x g O mole O 2 = 64 g O 2 27

Example: How many grams of hydrogen are in 12.0 moles of H 2 ? Set up: 12.0 moles H 2 x 1.01 g H mole H 2 = 12 g H 2 Remember sig figs 28

29 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

Example: How many grams of hydrogen are in 3.0 moles of H 2 O? Set up 3.0 mol H 2 O x 1.0 mol H 2 x 1.01 g H mol H 2 O 1.0 mol H 2 = 3.0 g H 2 Remember sig figs 30

31 molar mass Grams Moles Calculations with Molar Mass

32 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

33 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

34 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

35 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