Download MOLE Mass Volume Particles

Chapter 10: The Mole Sec. 1-3 NOTES
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The Mole
o Mole
 Abbreviated mol
 SI base unit used to measure the amount of a substance
 Equal to Avogadro’s number = 6.02 x 1023
 New Conversion Factor: 1 mol = 6.02 x 1023 particles of that substance
Steps to solve ANY dimensional analysis (unit conversion) problem:
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(1) Identify the units you are beginning with and want to end with
(2) Identify the conversion factors that will convert the starting units to the ending units
(3) Set up the problem starting with your beginning units
(4) Line up conversion factors to cancel out units you don’t want (units will cancel if you have the
same unit in the numerator and denominator)
(5) Plug the numbers into your calculator:
o Multiply all numbers in your numerators together
o Multiply all numbers in your denominators together
o Divide the number you get in the numerator by the number you get in the denominator
(6) Write final answer with the correct units
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Mole Conversions Overview
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Volume
1 mol = 22.4 L
1 mol = molar mass in g/mol
MOLE
1 mol = 6.02 x 1023 particles
Mass
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Converting between moles and particles
o A new conversion factor: 1 mol of particles = 6.02 x 1023 particles
o Example of converting between moles and particles:
 Q: How many molecules of sucrose are in 3.50 mol sucrose?
Particles
o Conversion Practice Problem
 How many moles are in 2.50 x 1020 atoms of Fe (iron)?
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Molar Mass
o Mass in grams of one mole of any pure substance
o Equal to the atomic mass of an element
o Found on Periodic Table in amu
o Units are g/mol
Converting between moles and mass
o Q: How many grams of Cu are in 3.00 mol of Cu?
Converting between mass and # of atoms
o Q: How many atoms of Au are in 31.1 g of Au?
o Calculations using Chemical Formulas
 Conversion Factors:
 CO2:
o 1 mol C atoms = 1 mol CO2
o 2 mol O atoms = 1 mol CO2
 Molar Mass of Compounds:
 Molar Mass of CO2 = 12.01 g/mol + 2(16.00 g/mol) = 44.01 g/mol CO2
 Example using Aluminum Oxide
 Q: How many moles of aluminum ions (Al3+) are in 1.25 mol of Al2O3?
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Example using HCl
 Q: How many moles of HCl are present in 35.0 g of HCl?
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Practice Problem
 Question: How many Na+ ions are present in a 2.25 g sample of sodium sulfite?
Example on the whiteboard using 35.6 g of AlCl3 (aluminum chloride)
o 1st Question: How many aluminum ions (Al3+) are present in 35.6 g AlCl3?
o 2nd Question: How many chloride ions (Cl-) are present?
o 3rd Question: What is the mass, in grams, of one formula unit of AlCl3?