Topic 4.1 The Mole and Stoichiometry

602,000,000,000,000,000,000,000 Individual atoms and molecules are too small to see and count individually. We keep track of individual particles by a counting unit called the “Mole”.

602,000,000,000,000,000,000,000 1 mole =602,000,000,000,000,000,000,000 1mole = 6.02 x Dozen = 12 1 deca = 10 1 ream = score =

1 mole = 6.02 x particles 2 moles = 2(6.02 x ) particles = 1.2 x particles 7 moles = 7(6.02 x ) particles = 4.2 x particles 0.5 moles = 0.5(6.02 x ) particles = 3.01 x particles moles = 0.025(6.02 x ) particles = 1.5 x particles

Ex: How many atoms are in moles of gold? 1 mole = 6.02 x particles multiply both sides by : (1 mole) = (6.02 x atoms) moles = x atoms = 6.02 x atoms

6 Number of grams in 1 mole (refer to PTOE) 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

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

8 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

9 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

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

11 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

12 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

13 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

14 molar mass Grams Moles Calculations with Molar Mass

15 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

16 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