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A warm up… 1 trio = 3 singers 1 six-pack Cola = 6 cans soda 1 dozen donuts = 12 donuts 1 gross of pencils = 144 pencils

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

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

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

Molar Mass Number of grams in 1 mole = 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

What are the number of atoms in mol of Al? 3.01 x Al atoms mol Al 6.02 x Al atoms 1 mol Al What are the number of moles of S if a sample of S contains 4.50 x S atoms? 7.5 mol S atoms 4.50 x S atoms 1 mol S 6.02 x S atoms Learning Check

Calculate the molar mass A. 1 mole of Br atoms =________ B.1 mole of Sn atoms =________ 79.9 g/mole g/mole

Molar Mass of Compounds Mass of compounds in g/mol = the sum of all of its atomic masses

CaCl 2 (1 mole Ca x 40.1 g/mol) + (2 moles Cl x 35.5 g/mol) 1 mole of CaCl 2 = g/mol N2O4N2O4 (2 moles N x 14.0 g/mole) + (4 moles O x 16.0 g/mole) 1 mole of N 2 O 4 = 92.0 g/mole Molar Mass of Compounds

Learning Check 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 (17 moles C x 12.0 g/mole) + (18 moles H x 1.0 g/mole) + (3 moles F x 19 g/mole) + (1 mole N x 14 g/mole) + (1 mole O x 16 g/mole)

Calculations with Molar Mass Grams Moles Atoms/Molecules Use 6.02 x (particles/mole) Use molar mass (grams/mole)

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Molar Mass Factors 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 15

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

Moles and Grams Aluminum is often used for the structure of light- weight bicycle frames. How many grams of Al are in 3.00 moles of Al? 1. Molar mass of 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 mol Al 27.0 g Al 1 mol Al Answer = 81.0 g Al

Learning Check 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?

Solution 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 1 mole aspartame 294 g aspartame Answer= moles of aspartame

Learning Check How many atoms of Aluminum are in 17 grams of Aluminum? 17 grams Al 1 mole Al 6.02 x atoms 27.0 grams Al 1 mole Al Answer= 3.8 x atoms of Al