12 g Carbon-12 = 1 mole of carbon atoms The Mole A mole (symbol: mol) is the amount of a substance that contains as many particles as there are atoms in exactly 12 g of carbon-12. 12 g Carbon-12 = 1 mole of carbon atoms

Mole (mol) of particles: Pair (2) Dozen (12) Gross (144) Mole (mol) of particles: (6.022 x 1023) Ream of paper (500)

One mole of copper = 63.55 g/mol A mole of copper atoms fits on this balance! One mole of copper = 63.55 g/mol How many atoms is this?

In the 1800's, an Italian scientist by the name of Amadeo Avogadro mathematically determined… …that a mole of atoms of any element is equal to the mass of that element in grams. A mole of Carbon atoms has a mass of 12.01 g. (Notice the periodic table)

AVOGADRO’S NUMBER 6.022  1023 6.022  1023 particles/mol equal to the number of particles in exactly one mole of a pure substance. 6.022  1023 particles/mol

CFU:

LETS TRY IT! 39 39 78 94 g

Remember this???? These dominos are set up in a pattern… can you see it? What would be the next 3 dominos in the series? Look only at the units, is this unit conversion set up like the dominos? After can you see it, pause… what are the next 3 dominos in the series?

Dimensional Analysis- Converting from a known unit to an unknown unit 3 steps: 1. What do I know? (“starting” underline) 2. What do I want to know? (circle “destination”) 3. How do I get there? (*equivalence statements) Example: Sarah wants to know how many milliseconds are in 360 seconds? (equivalence statement*: 1000 milliseconds = 1 second)

Example Problem #1: You have 2.00 grams of H2O, how many moles of H2O are present in 1 mole of this sample? Molar Mass of H2O = 18.01g 2.00 grams H2O 1 moles H2O 1 18.01 g/mol H2O

Example problem #2: Given 4.00 grams of nitrogen (N2), how many moles of the compound are present? Molar Mass N2 = 28.00 g N2 +2 H2  2 NH3 1 mole N2 4 grams N2 1 28.02 grams of N2

Calculations with Molar Mass Molar Ratio The molar ratio is made of the coefficients in front of the compounds in the balanced chemical equation.

Formula will use when converting from Moles of A to Moles of B: What you see below is a basic example of the layout of this type of problem. 1 Moles initially given in problem Moles of “given” from balanced equation Moles of what you want to “find” from balanced equation This number may or may not be included in actual equation

Steps to solving Mole to Mole problems: 1. Balance the chemical equation 2. The ratio of your coefficients = your equivalence statement

For every 1 mole of N2 there are 3 moles of H2

Example problem #1: 2KClO3 2KCl + 3O2 How many moles of Oxygen are produced by the decomposition of 6 moles of KClO3? 6 moles KClO3 3 moles O2 1 6 moles KClO3

Example Problem #2: Zn + 2HCl  ZnCl2 + H2 How many moles of H2 are produced from the reaction of 3 moles of Zn? 3 moles of Zn 1 mole of H2 1 1 mole of Zn

Example Problem #3: 1 C3H8 + 5O2  3CO2 + 4H2O How many moles of O2 are necessary to react completely with 4 moles of C3H8? 4 moles C3H8 5 moles O2 1 1 mole C3H8

PATH TRAVELLING FROM MOLES TO MOLECULES/ATOMS/PARTICLES Molar Ratio

1 Molecules of what you want to “find” from balanced equation Moles initially given in problem Moles of “given” from balanced equation Molecules of what you want to “find” from balanced equation This number may or may not be included in actual equation.

Example Problem #1: Convert 7.50 mole of O2 to molecules. 7.50 moles O2 6.02 x 1023 moles O2 1 1 mole O2

Example Problem #2: Convert 3.72 x 102 molecules to moles

How many molecules are in 3.05 moles of NH3? Example Problem #3: How many molecules are in 3.05 moles of NH3? 3.05 moles NH3 6.02 x 1023 molecules of NH3 1 1 mole NH3