The Mole 6.02 x 1023

Standard/Objective Know the quantity one mole is set by defining one mole of carbon 12 atoms to have a mass of exactly 12 grams. One mole = 6.02 x 1023 particles Know how to determine molar mass of a molecule and how to convert to moles, # of particles, or volume of gas at STP.

The mole is a counting unit 1 dozen = 12 1 ream = 500 1 gross = 144 1 mole = 602,000,000,000,000,000,000,000 6.02 X 1023 (in scientific notation)

Amedeo Avogadro (1776 – 1856) -studied quantities of gases & discovered that no matter what the gas was  the same number of molecules are present

Just How Big is a Mole? How long do you think it will take to count to 6.02x1023?

Just How Big is a Mole? If you spent a billion dollars a second, it would take you over 19 million years to spend a mole of dollars.

Just How Big is a Mole? Enough soft drink cans to cover the surface of the earth to a depth of over 200 miles. If you had Avogadro's number of unpopped popcorn kernels, and spread them across the United States of America, the country would be covered in popcorn to a depth of over 9 miles. If we were able to count atoms at the rate of 10 million per second, it would take about 2 billion years to count the atoms in one mole.

1 dozen cookies = 12 cookies 1 mole of cookies = 6.02 X 1023 cookies 1 dozen cars = 12 cars 1 mole of cars = 6.02 X 1023 cars 1 dozen Al atoms = 12 Al atoms 1 mole of Al atoms = 6.02 X 1023 atoms

How does the mass of a dozen cars compare to the mass of a dozen cookies? Note that the NUMBER is always the same, but the MASS is very different! Mole is abbreviated mol

Atomic Mass (amu) What is the atomic mass of: Na Ca Pb What is the molecular mass of: NaCl H2O FeCl3 Al(OH)3

Molar Mass (g/mol) The Mass of 1 mole (in grams) Equal to the numerical value of the average atomic mass (get from periodic table) *to the nearest whole # 1 mole of C atoms = 12.0 g 1 mole of Mg atoms = 24 g 1 mole of Cu atoms = 64 g

Molar Mass (g/mol) *Same number, different units: AMU  g mol

Calculations with Molar Mass Grams Moles

Converting Moles and Grams molar mass Grams Moles Converting 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? 3.00 moles Al ? g Al

Converting Moles and Grams molar mass Grams Moles How many grams of KCl are in 2.00 mol? How many grams of CO2 are in 0.500 mol? How many moles of Na are in 92.0 g? How many moles of H2O are in 54.0 g?

A Mole of Particles Contains 6.02 x 1023 Particles If you’re referring to an element… 1 mol Mg = 6.02 x 1023 Mg atoms 1 mol Au = 6.02 x 1023 Au atoms If you’re referring to a compound/molecule 1 mol NH3 = 6.02 x 1023 NH3 molecules 1 mol C9H8O4 = 6.02 x 1023 aspirin molecules Particles can be anything… 1 mol donuts = 6.02 x 1023 donuts

Avogadro’s Number as Conversion Factor 6.02 x 1023 particles 1 mole or 1 mole *a particle could be an atom OR a molecule Avogadro’s Number Particles Moles

Converting Between Moles & Particles Avogadro’s Number Particles Moles How many molecules would be in 2.00 mols of H2O? How many atoms would be in 10.0 moles of Al? How many molecules would be in 0.500 moles of CaCO3? How many molecules would be in 32.0 g of CH4?

Everything must go through Moles!!! Calculations molar mass Avogadro’s number Grams Moles particles Everything must go through Moles!!!

A Mole of Particles Contains 6.02 x 1023 Particles 1 dozen eggs = 12 eggs 1 dozen yolks & 1 dozen egg shells Or 12 yolks and 12 egg shells 1 mol NaCl = 6.02 x 1023 formula units NaCl 1 mol Na+ ions & 1 mol Cl- ions Or 6.02 x 1023 Na+ & 6.02 x 1023 Cl-

Learning Check 1. How many atoms of K are present in 78.0 g of K? 2. How many molecules of O2 are present in 96.0 g of oxygen? 3. What is the mass (in grams) of 1.806 X 1024 molecules of water (H2O)? 4. What is the mass of 9.03 X 1023 molecules of KNO3?

Moles and Gases At the same temperature and pressure, equal volumes of gases contain the same # of gas particles Molar Volume 1 mole gas (STP) = 22.4 L STP = 0° C and 1 atm STP – standard temperature and pressure atm – atmospheres, a measure of pressure

Learning Check A room with a volume of 2,240 L contains how many moles of air at STP? How many moles of hydrogen would be found in a 44.8 L container? A chemical reaction produces 4.00 moles of oxygen gas. What volume will that gas occupy at STP? What is the volume of 0.500 mol of nitrogen at STP?

Molecules MOLES Volume Mass Name of Conversion Factor Equation for Conversion Factor MOLES Name of Conversion Factor Equation for Conversion Factor Equation for Conversion Factor Name of Conversion Factor Volume Mass

Stoichiometry Organizer MASS MASS Molar Mass Molar Mass MOLES MOLES Ratio of Coefficients MOLECULES MOLECULES Avogadros # Avogadros # Molar Volume of Gas Molar Volume of Gas VOLUME VOLUME

QUIZ 11-8 Calculate the molecular mass of the following: 1. K2SO4 2. Ca(OH)2

QUIZ 11-8 Calculate the molecular mass of the following: 1. Na2CO3 2. Mg(NO3)2

QUIZ 11-8 Calculate the molecular mass of the following: 1. K3PO4 2. (NH4)2S

QUIZ 11-9 What is the mass of 2.00 mol of NH3? How many moles would be found in 132 g of CO2?

QUIZ 11-29 1. What is the mass of 2.00mol of (NH4)2O? 2. How many liters of ammonia gas (NH3) would weigh 51g?

QUIZ 12-1 1. What is the mass of 2.00mol of CO2? 2. How many liters of oxygen gas (O2) would weigh 64 g?

Review 1 : KClO3 Type of compound Name of compound Molecular mass How many grams of KClO3 in 2.5 moles? How many moles of KClO3 in 61.0 grams? How many molecules of KClO3 in 3.0 moles? How many molecules of KClO3 in 488g?

Review 2 : H3PO4 Type of compound Name of compound Molecular mass How many grams of H3PO4 in 2.5 moles? How many moles of H3PO4 in 147 grams? How many molecules of H3PO4 in 1.5 moles? How many molecules of H3PO4 in 294g?

Review 3 : N2O4 (g) How many moles of N2O4 in 5.6 liters? Type of compound Name of compound Molecular mass How many moles of N2O4 in 5.6 liters? How many liters of N2O4 in 184 grams?