Transcript Mole

12/19 Bell Work
Your eyes function by gathering light, focusing it,
and then the brain interprets the resulting
image.
Which would see most clearly in total darkness?
A leopard, a bat, or an owl? Neither? Why?
12/19 Schedule
• Finish Lab Practical (20 min)
• Counting by Mass Activity (20 min)
– p. 286
• Notes Ch 10.1 “Mole”?
All materials in for Tues-Wed?
Assignments:
1. Final Practical - TODAY
IA: Counting by Measuring Mass
Work in pairs on Inquiry Activity p. 286 in your
book. Show your work and answers on a
separate sheet of paper. (20 minutes)
Materials:
• Paperclips
• Balance
• Calculator
12/20 Bell Work
A survey of 50 editors showed that 20 could
write with their left hand and 10 could write
with either hand.
• How many could write with their right hand?
12/20 Schedule
• Signed Grade Sheets
• Ice Cream!
– Read lab, transport materials, get ice
TED and Scientist EC by WED!
Assignments:
1. Signed Grade Sheets - TODAY
12/21 Bell Work
Open your planner to p. 137. Read the
Amendments.
• What does it mean to “plead the 5th?”
12/21 Schedule
• Ice Cream!
– Head to Home Ec Room, get ice
– Split batch? Cookies again?
TED and Scientist EC by TODAY!
Assignments:
1. Signed Grade Sheets - LATE
12/22 Bell Work
If you had an extra $34,000 lying around, you
could buy all of the gifts from “Twelve Days of
Christmas.”
• True or false?
12/22 Schedule
• Clean desks and eat brownies
• Watch “Beware of Neuro-bunk”
Assignments:
1/9 Bell Work
• What is one thing you can do differently to be
better in school? Explain.
1/9 Schedule
• Notes Ch 10.1 “Chemical Quantities”
• Work on SR
Assignments:
1. Ch 10 “The Mole” SRs - TBA
Unit : The Mole
So many atoms, so few moles….
A mole in the hand is worth 6.02 x 1023 in
the bush.
Ch 10 “Chemical Quantities”
Chapter Objectives:
• Define “mole” as it relates to chemistry.
• Convert between moles, mass, and number of
particles in a substance.
• Distinguish between molecular and empirical
formulas.
Ch 10.1 “The Mole: A Measurement of
Matter”
Objectives:
• Describe methods of measuring the amount
of something.
• Define Avogadro’s Number and calculate
molar mass.
• Distinguish between atomic and molar mass.
10.1
The Mole: A Measurement of Matter
You could measure the grains
of sand in the sculpture by
counting each grain one, but
it would be much easier to
weigh the sand.
• Chemists use a similar
procedure to count
numbers of particles.
10.1
Measuring Matter
3 Measuring Matter Methods
•Count
• Mass
•Volume.
10.1
for Sample Problem 10.1
10.1
What is a Mole?
Mole or Avogadro’s Number
Number of representative particles, or
6.02  1023 .
–Representative particle refers to the
species present: atoms, molecules, or formula
units….
mole H2O = 6.02  1023 molecules
mole moles = 6.02  1023 moles
mole students = 6.02  1023 students
10.1
What is a Mole?
Converting Particles to Moles
– Mole (mol) of a substance is 6.02 
1023 and the SI unit for measuring the
amount of a substance.
– In honor of Amedeo Avogadro:
Italian nobleman, religious law &
physics professor
10.1
What is a Mole?
10.2
10.2
for Sample Problem 10.2
10.1
What is a Mole?
Converting Moles to Number of Particles
10.3
10.3
for Sample Problem 10.3
10.1
The Mass of a Mole of an Element
Molar Mass of an Element
•The atomic mass of an element in
grams is the mass of 1 mole.
1 atom C = 12.0107 amu
1 mol C = 12.0107 g
10.1
The Mass of a Mole of an Element
One molar mass of carbon, sulfur, mercury,
and iron are shown.
10.1
The Mass of a Mole of a
Compound
Molar Mass of a Compound
1. Find the grams of each element in one
mole of the compound.
2. Add the masses of the elements in the
compound.
10.1
The Mass of a Mole of a
Compound
• Substitute the grams for atomic mass
units. Thus 1 mol of SO3 has a mass of
80.1 g.
10.4
10.4
3rd Hr Welcome Back!
Jemila
Eliza
Devon
Austin
Kiara
Evan
1/10 Bell Work
Knowledge is knowing a tomato is a fruit.
Wisdom is not putting it in a fruit salad.
- Peter Kay, English comedian
• What is the difference between knowledge
and wisdom?
1/10 Schedule
• Notes Ch 10.1 “Quantities” and 10.2
“Relationships”
• Start Measure Molar Mass Lab
• Work on SR
Assignments:
1. Ch 10 “The Mole” SRs - TBA
for Sample Problem 10.4
10.1 Section Quiz.
1. Three common ways of measuring the amount
of something are by count, by mass, and
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by temperature.
by volume.
by area.
by density.
10.1 Section Quiz.
2. A mole of hydrogen gas, H2(g), contains 6.02 x
1023
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molecules.
atoms.
amu.
grams.
10.1 Section Quiz.
3. The atomic mass of fluorine is 19.0 amu, so the
molar mass is
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19.0 amu.
19.0 g.
6.02 x 1023 amu.
6.02 x 1023 g.
10.1 Section Quiz.
4. Calculate the molar mass of ammonium nitrate.
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45.02 g
80.05 g
60.06 g
48.05 g
Ch 10.2 “Mole-Mass and Mole-Volume
Relationships”
Objectives
• Describe how to convert the mass of a
substance to number of moles, and back.
• Identify the volume of a quantity of gas at STP
10.2
Mole–Mass and Mole–Volume Relationships
How can you guess the number of
jelly beans in a jar?
• Chemists use relationships
between the mole and quantities
like mass, volume, and number
of particles to solve problems.
10.2
The Mole–Mass Relationship
Converting between mass and moles…
10.5
10.5
for Sample Problem 10.5
10.6
10.6
for Sample Problem 10.6
10.2
The Mole–Volume Relationship
The Mole–Volume Relationship
– Avogadro’s hypothesis states equal volumes of
gases at the same temperature and pressure
contain equal numbers of particles.
10.2
The Mole–Volume Relationship
• “STP”
– Gas volume varies with temperature and pressure,
so scientists picked a standard.
– Standard temperature and pressure (STP) means
a temperature of 0°C and a pressure of 101.3 kPa,
or 1 atmosphere (atm).
10.2
The Mole–Volume Relationship
• At STP, 1 mol or, 6.02  1023 particles, of any
gas occupies a volume of 22.4 L.
– The quantity 22.4 L is called the molar volume of a gas.
10.2
The Mole–Volume Relationship
• Calculating Volume at STP
10.7
10.7
Review Conversions
Goal: Estimate the number of molecules in a
sugar cube or candy.
Procedure
Formula and molar mass
Mass of sample
Grams to moles
Moles to molecules
C12H22O11
______ g/mol
for Sample Problem 10.7
10.2
The Mole–Volume Relationship
• Calculating Molar Mass from Density
10.8
10.8
for Sample Problem 10.8
10.2
The Mole Road Map
• Copy onto your Periodic Table…
Measure Molar Mass Lab
• Figure out the molar mass of each substance. Use a
Periodic Table and the chemical formula.
• Measure out 1 mol of each substance. By density, 1
g water = 1 mL
• Compare your results with the other group.
• 20-25 min
10.2 Section Quiz.
1. Calculate the mass in grams of a sample
containing 1.85 x 1034 molecules of water.
1.
2.
3.
4.
3.07 x 1010 g
5.53 x 1011 g
188 g
8.46 x 103 g
10.2 Section Quiz.
2. Calculate the number of moles in a spoonful
of table sugar (C12H22O11) having a mass of
10.5 g.
1.
2.
3.
4.
32.6 mol
3.59  103 mol
3.07  10–3 mol
1.85  1022 mol
10.2 Section Quiz.
3. What is the volume of 0.35 mol of oxygen gas
at STP?
1.
2.
3.
4.
32 L
64 L
7.8 L
16 L