The Mole
PREPARED BY: TYPE YOUR NAME HERE
Use the mole concept to
express mass of
substances; and
S9MT -IIi - 19
As you may have
guessed, D is the correct
answer!!
Although a mole might be
cute and fuzzy, we are going
to focus on the Chemistry
concept.
Counting Atoms
 Chemistry is a quantitative science
- we need a "counting unit."
 The MOLE
 1 mole is the amount of substance
that contains as many particles
(atoms or molecules) as there are
in 12g of Carbon-12.
A mole is a counting unit.
Just like:
 12 eggs equals a dozen eggs
 144 pencils equals one gross of
pencils
 2 socks equals a pair of socks.
 500 sheets of paper equals one
ream
One mole equals 6.022 x 1023
particles
 So one mole of eggs would be 6.022 x 1023
eggs
 One mole of pencils would be 6.022 x 1023
pencils
 And so on...
How Big is a Mole?
One mole of marbles would cover the entire Earth
(oceans included) for a depth of three miles!!!!
e mole of $100 bills stacked one on top of another
uld reach from the Sun to Pluto and back 7.5 million
mes!!!!
would take light 9500 years to travel from the
tom to the top of a stack of 1 mole of $1 bills!!!!
Avogadro’s Number
 A MOLE of any substance contains as many elementary
units (atoms and molecules) as the number of atoms in
12 g of the isotope of carbon-12.
 This number is called AVOGADRO’s number NA = 6.02 x
1023
particles/mol
 The mass of one mole of a substance is called MOLAR
MASS
 Examples
H2 hydrogen 2 g/mol
He helium 4 g/mol
N2 nitrogen 28 g/mol
O2 oxygen 32 g/mol
CO2 carbon dioxide 44 g/mol
The 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
Note that the NUMBER is always the same,
but the MASS is very different!
A Mole of Particles
Contains 6.02 x 1023
particles
= 6.02 x 1023
C atoms
= 6.02 x 1023
H2O molecules
= 6.02 x 1023
NaCl “molecules”
6.02 x 1023
Na+
ions and
6.02 x 1023
Cl–
ions
1 mole C
1 mole H2O
1 mole NaCl
12
Using the mole concept is very much like using “dozen”.
Equivalence statement: 1 dozen eggs = 12 eggs
3.5 dozen eggs
1 dozen
12 eggs
( )
( ) = 42 eggs
How many eggs are in 3.5 dozen eggs?
3.5 mole Mg
( )
( ) = 2.1X1024
Mg atoms
How many Mg atoms are in 3.5 moles of Mg?
Equivalence statement: 1 mole Mg = 6.022X1023
Mg atoms
6.022X1023
Mg atoms
1 mole Mg
Mole Calculations I
 How many sodium atoms are in 0.120 mol Na?
• Step 1: we want atoms of Na
• Step 2: we have 0.120 mol Na
• Step 3: 1 mole Na = 6.02 × 1023
atoms Na
= 7.22 × 1022
atoms Na
0.120 mol Na ×
1 mol Na
6.02 × 1023
atoms Na
Mole Calculations I
 How many moles of potassium are in 1.25 × 1021
atoms K?
• Step 1: we want moles K
• Step 2: we have 1.25 × 1021
atoms K
• Step 3: 1 mole K = 6.02 × 1023
atoms K
= 2.08 × 10-3
mol K
1.25 × 1021
atoms K ×
1 mol K
6.02 × 1023
atoms K
Molar Mass
 The atomic mass of any substance expressed in
grams is the molar mass (MM) of that substance.
 The atomic mass of iron is 55.85 amu.
 Therefore, the molar mass of iron is 55.85 g/mol.
 Since oxygen occurs naturally as a diatomic, O2,
the molar mass of oxygen gas is 2 times 16.00 g
or 32.00 g/mol.
Learning Check
1. Number of atoms in 0.500 mole of Al
a) 500 Al atoms
b) 6.02 x 1023
Al atoms
c) 3.01 x 1023
Al atoms
2.Number of moles of S in 1.8 x 1024
S atoms
a) 1.0 mole S atoms
b) 3.0 mole S atoms
c) 1.1 x 1048
mole S atoms
Calculating Molar Mass
 The molar mass of a substance is the sum of the
molar masses of each element.
 What is the molar mass of magnesium nitrate,
Mg(NO3)2?
 The sum of the atomic masses is:
24 + 2(14 + 16 + 16 + 16) =
24 + 2(62) = 148 amu
 The molar mass for Mg(NO3)2 is 148 g/mol.
Mole Calculations II
 Now we will use the molar mass of a compound
to convert between grams of a substance and
moles or particles of a substance.
6.02 × 1023
particles = 1 mol = molar mass
 If we want to convert particles to mass, we must
first convert particles to moles and than we can
convert moles to mass.
Mass-Mole Calculations
 What is the mass of 1.33 moles of titanium, Ti?
 We want grams, we have 1.33 moles of titanium.
 Use the molar mass of Ti: 1 mol Ti = 47.88 g Ti
= 63.7 g Ti
1.33 mole Ti ×
47.88 g Ti
1 mole Ti
Mole Conversions
It’s time for some mole jokes!
How does Avogadro talk to his friends?
By E-Mole! Hahaha
Where did Avogadro go on Saturday?
The shopping mole.. Wow these are funny!
Why did Avogadro look forward to the year 2000?
It was the start of the new molennium!!!
What was Avogadro's favorite sport?
Golf - because he always got a mole-in-one.
 Content, images, text, etc. used belong to the rightful owner. No copyright
infringement intended.

G9 Science Q2- Week 7-Mole-Concept-Presentation.pptx

  • 1.
    The Mole PREPARED BY:TYPE YOUR NAME HERE
  • 2.
    Use the moleconcept to express mass of substances; and S9MT -IIi - 19
  • 3.
    As you mayhave guessed, D is the correct answer!! Although a mole might be cute and fuzzy, we are going to focus on the Chemistry concept.
  • 4.
    Counting Atoms  Chemistryis a quantitative science - we need a "counting unit."  The MOLE  1 mole is the amount of substance that contains as many particles (atoms or molecules) as there are in 12g of Carbon-12.
  • 5.
    A mole isa counting unit. Just like:  12 eggs equals a dozen eggs  144 pencils equals one gross of pencils  2 socks equals a pair of socks.  500 sheets of paper equals one ream
  • 6.
    One mole equals6.022 x 1023 particles  So one mole of eggs would be 6.022 x 1023 eggs  One mole of pencils would be 6.022 x 1023 pencils  And so on...
  • 7.
    How Big isa Mole? One mole of marbles would cover the entire Earth (oceans included) for a depth of three miles!!!! e mole of $100 bills stacked one on top of another uld reach from the Sun to Pluto and back 7.5 million mes!!!! would take light 9500 years to travel from the tom to the top of a stack of 1 mole of $1 bills!!!!
  • 8.
    Avogadro’s Number  AMOLE of any substance contains as many elementary units (atoms and molecules) as the number of atoms in 12 g of the isotope of carbon-12.  This number is called AVOGADRO’s number NA = 6.02 x 1023 particles/mol  The mass of one mole of a substance is called MOLAR MASS  Examples H2 hydrogen 2 g/mol He helium 4 g/mol N2 nitrogen 28 g/mol O2 oxygen 32 g/mol CO2 carbon dioxide 44 g/mol
  • 9.
    The Mole  1dozen 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 Note that the NUMBER is always the same, but the MASS is very different!
  • 10.
    A Mole ofParticles Contains 6.02 x 1023 particles = 6.02 x 1023 C atoms = 6.02 x 1023 H2O molecules = 6.02 x 1023 NaCl “molecules” 6.02 x 1023 Na+ ions and 6.02 x 1023 Cl– ions 1 mole C 1 mole H2O 1 mole NaCl
  • 11.
    12 Using the moleconcept is very much like using “dozen”. Equivalence statement: 1 dozen eggs = 12 eggs 3.5 dozen eggs 1 dozen 12 eggs ( ) ( ) = 42 eggs How many eggs are in 3.5 dozen eggs? 3.5 mole Mg ( ) ( ) = 2.1X1024 Mg atoms How many Mg atoms are in 3.5 moles of Mg? Equivalence statement: 1 mole Mg = 6.022X1023 Mg atoms 6.022X1023 Mg atoms 1 mole Mg
  • 12.
    Mole Calculations I How many sodium atoms are in 0.120 mol Na? • Step 1: we want atoms of Na • Step 2: we have 0.120 mol Na • Step 3: 1 mole Na = 6.02 × 1023 atoms Na = 7.22 × 1022 atoms Na 0.120 mol Na × 1 mol Na 6.02 × 1023 atoms Na
  • 13.
    Mole Calculations I How many moles of potassium are in 1.25 × 1021 atoms K? • Step 1: we want moles K • Step 2: we have 1.25 × 1021 atoms K • Step 3: 1 mole K = 6.02 × 1023 atoms K = 2.08 × 10-3 mol K 1.25 × 1021 atoms K × 1 mol K 6.02 × 1023 atoms K
  • 14.
    Molar Mass  Theatomic mass of any substance expressed in grams is the molar mass (MM) of that substance.  The atomic mass of iron is 55.85 amu.  Therefore, the molar mass of iron is 55.85 g/mol.  Since oxygen occurs naturally as a diatomic, O2, the molar mass of oxygen gas is 2 times 16.00 g or 32.00 g/mol.
  • 15.
    Learning Check 1. Numberof atoms in 0.500 mole of Al a) 500 Al atoms b) 6.02 x 1023 Al atoms c) 3.01 x 1023 Al atoms 2.Number of moles of S in 1.8 x 1024 S atoms a) 1.0 mole S atoms b) 3.0 mole S atoms c) 1.1 x 1048 mole S atoms
  • 16.
    Calculating Molar Mass The molar mass of a substance is the sum of the molar masses of each element.  What is the molar mass of magnesium nitrate, Mg(NO3)2?  The sum of the atomic masses is: 24 + 2(14 + 16 + 16 + 16) = 24 + 2(62) = 148 amu  The molar mass for Mg(NO3)2 is 148 g/mol.
  • 17.
    Mole Calculations II Now we will use the molar mass of a compound to convert between grams of a substance and moles or particles of a substance. 6.02 × 1023 particles = 1 mol = molar mass  If we want to convert particles to mass, we must first convert particles to moles and than we can convert moles to mass.
  • 18.
    Mass-Mole Calculations  Whatis the mass of 1.33 moles of titanium, Ti?  We want grams, we have 1.33 moles of titanium.  Use the molar mass of Ti: 1 mol Ti = 47.88 g Ti = 63.7 g Ti 1.33 mole Ti × 47.88 g Ti 1 mole Ti
  • 19.
  • 20.
    It’s time forsome mole jokes! How does Avogadro talk to his friends? By E-Mole! Hahaha Where did Avogadro go on Saturday? The shopping mole.. Wow these are funny! Why did Avogadro look forward to the year 2000? It was the start of the new molennium!!! What was Avogadro's favorite sport? Golf - because he always got a mole-in-one.
  • 21.
     Content, images,text, etc. used belong to the rightful owner. No copyright infringement intended.

Editor's Notes

  • #4 http://web.syr.edu/~nstefanc/New%20Counting.JPG http://www.wildcru.org/research/farming/moles/mole1.jpg
  • #5 A more precise value of Avagadro’s number = 6.022045 E23. How could you determine the number of sugar crystals in a bowl of sugar? Is it possible to get a reasonably close estimate?