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Mole Lecture. = 6.022 x 10 23 amu. x. grams. amu. 12.01 amu. A. Definitions: 1. Molar Mass (Gram atomic weight): the mass in ______ that is numerically equal to the mass in _____. a. mass of 1 carbon atom _________ mass of 1 mole of C _______
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= 6.022 x 10 23 amu x grams amu 12.01 amu A. Definitions: 1. Molar Mass (Gram atomic weight): the mass in ______ that is numerically equal to the mass in _____. a. mass of 1 carbon atom _________ • mass of 1 mole of C _______ 2. Mole = ____________ of anything. 3. Avogadro’s number = ___________ 4. Molar Mass = The mass in grams of ________ (6.02 x 1023 atoms or molecules). 5. What is the relationship between atomic mass units and grams? 12.01 g Avogadro’s # 6.022 x 1023 1 mole 1 mole C = 12.011 g 0.0005486 amu 1 g 9.11 x 10 -28 g
Molar # atoms Mol Mass (g) Mass Must go through the mole Periodic Table x = 7.95 x 10 -23 g x 6.022 x 1023 B. Calculations based on the mole. 1. What is the mass of a Titanium atom in amu? Grams? 2. What is the mass of one mole of Titanium? 1 atom Ti = 47.88 amu 1 mol Ti 47.88 g 1 atom Ti 1 mol Ti 6.022 x 1023 atoms (If no initial value is provided, round answer to 3 sig figs) 1 mol Ti = 47.88 g
x = 7.95 mol S x x = 4.79 x 1024 atoms S = 1.66 x 10-15 mol U x = 3.95 x 10 –13 g U 1 mol S 255 g 32.07 g 3. How many (a) moles and (b) atoms of sulfur are there in 255 g of Sulfur? 4. How many (a) moles and (b) grams of Uranium are there in a billion U atoms? 6.022 x 1023 atoms S 7.95 mol S 1 mol S 1 mol U 1 x 109 atoms U 6.022 x 1023 atoms U 238.03 g 1.66 x 10-15 mol U 1 mol U (If no initial value is provided, round answer to 3 sig figs)
x x x x x x = 4.67 x 10-23 g Si = 8.0 x 10-20 g S = 2.90 x 1022 atoms Cu 5. How many Cu atoms are there in a solid copper penny that has a mass of 3.06 grams? 6.022 x 1023 atoms Cu 1 mol Cu 3.06 g 1 mol Cu 63.55 g 6. What is the mass of one atom of silicon in (a) amu (b) grams (c) pounds? 7. What is the mass of 1500 sulfur atoms in grams? (a) 1 atom = 28.09 amu Si 1 mol Si 28.09 g (b) 1 atom Si 1 mol Si 6.022 x 1023 atoms Si (c) 1.03 x 10-25 lb. Si 32.07 g 1 mol S 1500 atoms S 6.022 x 1023 atoms S 1 mol S
= 294.14 g/mole sum atoms grams IV. Molecular Mass (weight) A. The molecular mass is the _____ of the atomic masses in (amu) of all the ______ in a molecule. The molar mass is the same mass but in ______. 1. What is the molecular mass of benzene, C6H6? What is the molar mass? B. Substances that do not form molecules such as ionic solids do not have a molecular weight; they have formulaweights. 1. What is the formula mass of aluminum sulfite? Al2(SO3)3 the molar mass? 78.12 g = 1 mole 6(12.01) + 6(1.01) = 78.12 amu or 78.12 g/mole 6 C 6 H distributive 2 (Al) + 3 (S) + 9 (O) 2 (26.98) + 3 (32.06) + 9 (16.00) = 294.14 amu
= 227.14 amu = 410.38 amu 7 (C) + 5 (H) + 3 (N) + 6 (O) 7 (12.01) + 5 (1.01) + 3 (14.01) + 6 (16.00) 2. Calculate the molecular mass of TNT, C7H5N3O6. 3. What is the formula mass (amu) of Cr(OH)2 18 H2O? (Cr) + 38 (H) + 20 (O) (52.00) + 38 (1.01) + 20 (16.00)
VI. MOLES II: Moles & Formula A. General Information: 1. 1 mole = ____________ number of anything. Avogadro’s number = ___________. 2. 1 mole of atoms = ___________ atoms. 1 mole of molecules = __________ molecules. 3. The atomic weight of oxygen is _____ amu. a. One oxygen atom has a mass of _____ amu. b. One mole of oxygen atoms (6.02 x 1023 atoms) has a mass of _______. This is called the _____ atomic weight. 6.022 x 1023 6.022 x 1023 6.022 x 1023 6.022 x 1023 16.00 16.00 16.00 g gram
Atoms Molecules Formula Units Particles 6.022 x 1023 Molar Mass Mass (g) Mol amu single grams 1 mol 4. The molecular weight (mass) expressed in ____ represents the mass of a ______ molecule, while the molecular weight expressed in ______ represents the mass of _____ of molecules; this is called the gram molecular weight. 5. Substance that do not form molecules, such as ionic solids, do not have a molecular weight. They have a formula weight that when given in grams is called the gram formula weight and represents the mass of _____ or the compound. This is used in ionic substances. 6. Road Map: 1 mol
x x x = 2.99 x 10-23 g Iron (III)/Ferric carbonate 2 mol Fe B. Sample Problems 1. 0.500 moles of Fe2(CO3)3 (________________________) contains how many moles of a. Fe b. C c. O • Calculate the mass of one water molecule in • amu (b) grams 0.500 mol = 1.00 mol 1 mol Fe2(CO3)3 3 x 0.500 9 x 0.500 1.50 mol 4.50 mol 2 (1.01) + 1 (16.00) = 18.02 amu 1 mol 18.02 g 1 molecule 1 mol 6.022 x 1023 molec
x = 81.1 g H2O x = 2.71 x 1024 molec. H2O • (a) How much does 4.50 moles of water weigh in grams? (b) How many molecules is this? 18.02 g H2O 4.50 mol H2O 1 mol H2O 6.022 x 1023 molec H2O 4.50 mol H2O 1 mol H2O