Chapter 10 Chemical Quantities 10.1 The Mole: A Measurement of Matter 10.2 Mole-Mass and Mole-Volume Relationships 10.3 Percent Composition and Chemical Formulas Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Mass Relationship What is the mass of one mole of Iodine? Look at the periodic table – the atomic mass of iodine is 126.905 g so that is the mass of one mole of iodine. If asking about iodine gas (a diatomic molecule) it would be twice that = 253.81 g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Mass Relationship 2. What is the molar mass of C2H6? You have 2 atoms of carbon and 6 of hydrogen. Look at the periodic table for the molar mass of each element: Carbon’s mass is 12.0111g and Hydrogen’s mass is 1.00794g So, (2 X 12.0111g) + (6 X 1.00794g) = 30.0698g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 3

The Mole-Mass Relationship 3. What is the molar mass of Mg(NO2)2? You have 1 magnesium atom, 2 nitrogen atoms and 4 oxygen atoms. Look at the periodic table for the molar mass of each element: Magnesium is 24.305g, nitrogen is 14.0067g, and oxygen is 15.9994g. So, 24.305g + (2X14.0067g) + (4X15.9994g) = 116.32g 5 sig figs!! Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 4

The Mole-Mass Relationship Molar mass is used to convert between mass and moles. molar mass = 1 mol molar mass 1 mol and Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Converting Moles to Mass Sample Problem 10.5 Converting Moles to Mass 1. What is the mass, in grams, of 2.1 moles of Al? 2. What is the mass, in grams of 2.1 moles of AlCl3 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Converting Moles to Mass Sample Problem 10.5 Converting Moles to Mass 1. What is the mass, in grams, of 2.1 moles of Al? 57 g 2. What is the mass, in grams of 2.1 moles of AlCl3 280 g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Converting Mass to Moles Sample Problem 10.6 Converting Mass to Moles How many moles are in 0.37 g of boron? How many moles are in 75 g of dinitrogen trioxide? Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Converting Mass to Moles Sample Problem 10.6 Converting Mass to Moles How many moles are in 0.37 g of boron? 0.034 mol B How many moles are in 75 g of dinitrogen trioxide? 0.99 mol N2O3 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Mass Relationship Do Now: How many moles of NaCl are in 100.0 grams of NaCl? How many molecules of CO2 are in 100.0 grams of CO2? Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Volume Relationship Avogadro’s Hypothesis At STP, 1 mol of any gas occupies 22.4 L. STP - Standard temperature & pressure 0°C and 101.3 kPa, or 1 atmosphere (atm). Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Mass Relationship Molar volume of a gas can be used to convert between volume and moles. molar volume of a gas = 22.4 L = 1 mol 22.4 L 1 mol and Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Volume Relationship Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the volume, in liters, of 3.7 mol N2 gas at STP. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the volume, in liters, of 3.7 mol N2 gas at STP. 82.9 L N2 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the number of moles of SO2 in 67.2 L SO2, at STP. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the number of moles of SO2 in 67.2 L SO2, at STP. 3.0 mol SO2 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Volume Relationship Calculating Molar Mass and Density Density and molar volume at STP can be used to calculate molar mass of a gas. Molar mass = Density * Molar Volume Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Calculating the Molar Mass of a Gas at STP Sample Problem 10.8 Calculating the Molar Mass of a Gas at STP A gaseous compound containing sulfur and oxygen has a density of 3.58 g/L at STP. What is the molar mass of the compound? Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Calculating the Molar Mass of a Gas at STP Sample Problem 10.8 Calculating the Molar Mass of a Gas at STP A gaseous compound containing sulfur and oxygen has a density of 3.58 g/L at STP. What is the molar mass of the compound? 80.2 g/mol Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The Mole-Mass Relationship Do Now: Table sugar, or sucrose, has the chemical formula C12H22O11. 1 teaspoon of sugar has a mass of 4.2 grams. How many moles of sugar molecules are in 1 teaspoon of sugar? How many sugar molecules are in 1 teaspoon of sugar? Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

END OF 10.2 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Converting Moles to Mass Sample Problem 10.5 Converting Moles to Mass 1. What is the mass, in grams, of 2.1 moles of Al? 2.1 mol X molar mass of Al = 1 mol 26.98154 g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 23

Converting Moles to Mass Sample Problem 10.5 Converting Moles to Mass 1. What is the mass, in grams, of 2.1 moles of Al? 57 g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 24

Converting Moles to Mass Sample Problem 10.5 Converting Moles to Mass 2. What is the mass, in grams of 2.1 moles of AlCl3 2.1 mol X molar mass of AlCl3 1 mol 133.34g = 26.98154 g + 3(35.453g)=133.34g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 25

Converting Moles to Mass Sample Problem 10.5 Converting Moles to Mass 2. What is the mass, in grams of 2.1 moles of AlCl3 280 g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 26

Converting Mass to Moles Sample Problem 10.6 Converting Mass to Moles How many moles are in 0.37 g of boron? 0.37g X 1 mol = molar mass of B 10.81 g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 27

Converting Mass to Moles Sample Problem 10.6 Converting Mass to Moles How many moles are in 0.37 g of boron? 0.034 mol B Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 28

Converting Mass to Moles Sample Problem 10.6 Converting Mass to Moles How many moles are in 75 g of dinitrogen trioxide? 75g X 1 mol = mol mass of N2O3 76.0116 g 2 (14.0067g) + 3 (15.9994g) = 76.0116 g Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 29

Converting Mass to Moles Sample Problem 10.6 Converting Mass to Moles How many moles are in 75 g of dinitrogen trioxide? 0.99 mol N2O3 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 30

The Mole-Mass Relationship How many moles of NaCl are in 100.0 grams of NaCl? Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 31

The Mole-Mass Relationship How many moles of NaCl are in 100.0 grams of NaCl? 100.0 g X 1 mol/molar mass of NaCl= 100.0 g X 1 mol/(22.98977g + 35.453g) = 100.0g X 1 mol/58.443g = 1.711 mol Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 32

The Mole-Mass Relationship 2. How many molecules of CO2 are in 100.0 grams of CO2? 100.0 g X 1 mol/molar mass of CO2 = 100.0 g X 1 mol/ (12.0111 g + 2(15.9994 g) ) = 100.0 g X 1 mol/44.0099g = 2.722 mol 2.722 mol X 6.02X1023 molecules / 1 mol = 1.639 X 1024molecules Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 33

The Mole-Volume Relationship Avogadro’s Hypothesis At STP, 1 mol of any gas occupies 22.4 L. STP - Standard temperature & pressure 0°C and 101.3 kPa, or 1 atmosphere (atm). Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 34

The Mole-Mass Relationship Molar volume of a gas can be used to convert between volume and moles. molar volume of a gas = 22.4 L = 1 mol 22.4 L 1 mol and Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 35

The Mole-Volume Relationship Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 36

Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the volume, in liters, of 3.70 mol N2 gas at STP 3.70 mol X 22.4 L = 1 mol Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 37

82.9 L N2 Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the volume, in liters, of 3.70 mol N2 gas at STP. 82.9 L N2 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 38

Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the number of moles of SO2 in 67.2 L SO2, at STP. 67.2 L X 1 mole/22.4 L = Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 39

Calculating Gas Quantities at STP Sample Problem 10.7 Calculating Gas Quantities at STP Determine the number of moles of SO2 in 67.2 L SO2, at STP. 3.00 mol SO2 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 40

The Mole-Volume Relationship Calculating Molar Mass and Density Density and molar volume at STP can be used to calculate molar mass of a gas. Molar mass = Density * Molar Volume Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 41

Calculating the Molar Mass of a Gas at STP Sample Problem 10.8 Calculating the Molar Mass of a Gas at STP A gaseous compound containing sulfur and oxygen has a density of 3.58 g/L at STP. What is the molar mass of the compound? Molar Mass = Density X Molar Volume Molar Mass = 3.58g/L X 22.4 L = Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 42

Calculating the Molar Mass of a Gas at STP Sample Problem 10.8 Calculating the Molar Mass of a Gas at STP A gaseous compound containing sulfur and oxygen has a density of 3.58 g/L at STP. What is the molar mass of the compound? 80.2 g/mol Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 43

Table sugar, or sucrose, has the chemical formula C12H22O11. 1 teaspoon of sugar has a mass of 4.2 grams. How many moles of sugar molecules are in 1 teaspoon of sugar? Grams to moles: 4.2 grams X 1 mole/(molar mass of C12H22O11 )= moles C12H22O11 Molar mass of C12H22O11 = 12(12.0111g) + 22(1.00794) + 11(15.9994) = = 342.3 g 4.2 g X 1mol/342.3g = 0.012 moles Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 44

Moles X molecules/mole = molecules Table sugar, or sucrose, has the chemical formula C12H22O11. How many sugar molecules are in 1 teaspoon of sugar? Moles to molecules: Moles X molecules/mole = molecules 0.012 moles X 6.02X1023 molecules/1 moles = 7.2 X 1021 molecules Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 45

END OF 10.2 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. . 47