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10: The Mole Editor:MoleEditor: Kerry Demond ThereDemondThere are many
The mole is simply another way to measure mass. A mole contains a certain amount of particles, just as a dozen eggs contains twelve eggs. In this section, you will learn about the various things we can learn through an understanding of the mole.
10.1: The Mole-A Measurement of Matter
The Mole-Volume Relationship (300)
Kendall Lavin-Parsons
Moles of solid and liquids are not even
Gases are even more different
Volume of moles of gases are more predictable
Avogadro’s hypothesis = equal volume of gases at the same temperature and pressure contain equal numbers of particles
All particles in gas are very spread apart with a large gap of time in between
This stands true for both large and small particles
Volume of gas varies with change in temperature
EX: when you take a balloon of helium outside and it shrinks
Standard temperature and pressure (STP) = temperature of 0 degrees Celsius, pressure of 101.3 kPa, 1 atmosphere (atm)
EX: in STP 6.02 x 10 ^23 representative particles of gasses occupies a volume of 22.4 Liters
The quantity in Liters is known as the Molar Volume
Calculating Volume at STP (301)
Phil Royal
{http://miznerscience.org/files/first_semester_files/molar_roadmap.GIF}
Practice Problems
Frank "the Tank" Morley
Calculate the volume:
assume Assume these are
.375 moles
.780 moles
The Percent Composition of a Compound (305-306)
Brett Chatfield
The Percent Composition of a Compound
- If you have ever had experience with cutting grass, you know that the percent of fertilizer used is very important. In the spring, you may use a fertilizer with a high concentration of nitrogen to make it green. In the fall, you may want potassium to strengthen it.
- The relative amounts of the elements in a compound are expressed as the percent composition or the percent by mass of each element in the compound. The percent composition of a compound is the percent value of each element in the compound.
For Additional Help:
http://www.youtube.com/watch?v=xbEeyT8nK84
Practice Worksheets:
http://misterguch.brinkster.net/PRA023.pdfA Practice Worksheet
Percent Composition from the Chemical Formula (307)
Chris Hart
chemical formula. The
The subscripts in that compound. The
The sum of molar mass. Using
Using the individual the compound. Divide
Divide the mass
%mass = mass of element in 1 mol compound x 100%
molar mass of compound
Molecular Formulas (311-312)
Nic Cunha
Molecular Formula
Many chemicals have the same empirical formulas such as ethyne and benzene, both have the empirical formula CH. But these compounds, as well as many others, have different molar masses. Their molar masses are simple whole number multiples of the molar masses of the empirical formula, CH. The Molecular Formula od a compound I either the same as its experimentally determined empirical formula, or it’s a simple whole number multiple of its empirical formula. Once you have determined the empirical formula of your compound, you can determine its molecular formula, but you must know its molar mass. From the Empirical formula you can calculate the empirical formula mass (efm)à simply the molar mass represented by the empirical formula. Then you can divide the experimentally determined molar mass by the efm. This gives the number of empirical formula units in a molecule of the compound and is the multiplier to convert the empirical formula to the molecular formula.
For example:
{molecular_formula_pic.png}
http://www.youtube.com/watch?v=nslC7lOSc7Y
By: Nic Cunha

10: The MoleEditor:Mole Editor: Kerry DemondThereDemond There are many
The mole is simply another way to measure mass. A mole contains a certain amount of particles, just as a dozen eggs contains twelve eggs. In this section, you will learn about the various things we can learn through an understanding of the mole.
10.1: The Mole-A Measurement of Matter
The Mole-Volume Relationship (300)
Kendall Lavin-Parsons
Moles of solid and liquids are not even
Gases are even more different
Volume of moles of gases are more predictable
Avogadro’s hypothesis = equal volume of gases at the same temperature and pressure contain equal numbers of particles
All particles in gas are very spread apart with a large gap of time in between
This stands true for both large and small particles
Volume of gas varies with change in temperature
EX: when you take a balloon of helium outside and it shrinks
Standard temperature and pressure (STP) = temperature of 0 degrees Celsius, pressure of 101.3 kPa, 1 atmosphere (atm)
EX: in STP 6.02 x 10 ^23 representative particles of gasses occupies a volume of 22.4 Liters
The quantity in Liters is known as the Molar Volume
Calculating Volume at STP (301)
Phil Royal
{http://miznerscience.org/files/first_semester_files/molar_roadmap.GIF}
Practice Problems
Frank "the Tank" Morley
Calculate the volume:
assume these are all the moles of gaseous elements: 1 mole fills 22.4 L at STP
The Percent Composition of a Compound (305-306)
Brett Chatfield
The Percent Composition of a Compound
- If you have ever had experience with cutting grass, you know that the percent of fertilizer used is very important. In the spring, you may use a fertilizer with a high concentration of nitrogen to make it green. In the fall, you may want potassium to strengthen it.
- The relative amounts of the elements in a compound are expressed as the percent composition or the percent by mass of each element in the compound. The percent composition of a compound is the percent value of each element in the compound.
http://www.youtube.com/watch?v=xbEeyT8nK84
Practice Worksheets:
A helpful practice worksheethttp://misterguch.brinkster.net/PRA023.pdf
Percent Composition from the Chemical Formula (307)
Chris Hart
chemical formula.
TheThe subscripts in that compound.
TheThe sum of molar mass.
UsingUsing the individual the compound.
DivideDivide the mass
%mass = mass of element in 1 mol compound x 100%
molar mass of compound
Molecular Formulas (311-312)
Nic Cunha
Molecular Formula
Many chemicals have the same empirical formulas such as ethyne and benzene, both have the empirical formula CH. But these compounds, as well as many others, have different molar masses. Their molar masses are simple whole number multiples of the molar masses of the empirical formula, CH. The Molecular Formula od a compound I either the same as its experimentally determined empirical formula, or it’s a simple whole number multiple of its empirical formula. Once you have determined the empirical formula of your compound, you can determine its molecular formula, but you must know its molar mass. From the Empirical formula you can calculate the empirical formula mass (efm)à simply the molar mass represented by the empirical formula. Then you can divide the experimentally determined molar mass by the efm. This gives the number of empirical formula units in a molecule of the compound and is the multiplier to convert the empirical formula to the molecular formula.
For example:
Empirical formula of hydrogen peroxide is HO. Its efm is 17.0 g/mol. The molar mas of H­2O2 is 34.0 g/mol.
34.0g/mol = 2
17.0 g/mol
To obtain the molecular formula of hydrogen peroxide from its empirical formula, multiply the subscripts in the empirical formula by 2 (the number above). (HO) x2= H­2O2.
{molecular_formula_pic.png}
http://www.youtube.com/watch?v=nslC7lOSc7Y
By: Nic Cunha

ChapterChapter 10: The Mole Editor:MoleEditor: Kerry Demond ThereDemondThere are many
The mole is simply another way to measure mass. A mole contains a certain amount of particles, just as a dozen eggs contains twelve eggs. In this section, you will learn about the various things we can learn through an understanding of the mole.
10.1: The Mole-A Measurement of Matter
The Mole-Volume Relationship (300)
Kendall Lavin-Parsons
Moles of solid and liquids are not even
Gases are even more different
Volume of moles of gases are more predictable
Avogadro’s hypothesis = equal volume of gases at the same temperature and pressure contain equal numbers of particles
All particles in gas are very spread apart with a large gap of time in between
This stands true for both large and small particles
Volume of gas varies with change in temperature
EX: when you take a balloon of helium outside and it shrinks
Standard temperature and pressure (STP) = temperature of 0 degrees Celsius, pressure of 101.3 kPa, 1 atmosphere (atm)
EX: in STP 6.02 x 10 ^23 representative particles of gasses occupies a volume of 22.4 Liters
The quantity in Liters is known as the Molar Volume
Calculating Volume at STP (301)
Phil Royal
{http://miznerscience.org/files/first_semester_files/molar_roadmap.GIF}
Practice Problems
Frank "the Tank" Morley
Calculate the volume:
assume these are all the moles of gaseous elements: 1 mole fills 22.4 L at STP
The Percent Composition of a Compound (305-306)
Brett Chatfield
The Percent Composition of a Compound
- If you have ever had experience with cutting grass, you know that the percent of fertilizer used is very important. In the spring, you may use a fertilizer with a high concentration of nitrogen to make it green. In the fall, you may want potassium to strengthen it.
- The relative amounts of the elements in a compound are expressed as the percent composition or the percent by mass of each element in the compound. The percent composition of a compound is the percent value of each element in the compound.
http://www.youtube.com/watch?v=xbEeyT8nK84
Practice Worksheets:
http://misterguch.brinkster.net/PRA023.pdfA helpful practice worksheet
Percent Composition from the Chemical Formula (307)
Chris Hart
chemical formula. The
The subscripts in that compound. The
The sum of molar mass. Using
Using the individual the compound. Divide
Divide the mass
%mass = mass of element in 1 mol compound x 100%
molar mass of compound

Chapter Chapter 10: The Mole
Editor: Editor: Kerry DemondHey guys, wiki is due THURSDAY, MARCH 8 by 8:00 pm. I'm willing to push it backDemond There are many different systems of measurment in the world, each used in a bit if someone really needs me to, but dovariety of ways. Teachers measure your bestgrade in points; doctors measure your height in inches.
The mole is simply another way to get it done on time. If you can findmeasure mass. A mole contains a video to support your topic (or better yet, FILMcertain amount of particles, just as a videodozen eggs contains twelve eggs. In this section, you will learn about your topic) it would be great.the various things we can learn through an understanding of the mole.
10.1: The Mole-A Measurement of Matter
Measuring Matter (287-288)
2.0 kg htmldiff2apples:1 dozen apples
1 dozen htmldiff3apples: 0.20 bushel apples
Count (289) Dan
Dan Lynch
In this section you learn how to find the mass of a sum of objects.
This is easy and we all learned it in class but I'll give a few examples of how to do it with simple dimensional analysis.
Next you want to make sure your answer makes sense.
A review of dimensional analysis go to pg 289 OR pg R66 in the text book, both are helpful.
Dan Lynch
What is a Mole? (290)
Siri Devlin
Representative particle- the species present in a substance: usually atoms, molecules, or formula units
⌘ a mole of any substance contains Avagadro’s number of representative particles, or 6.02X 10^23 representative particles
Converting Moles to Number of Particles to Moles
(291-293) Ben Ross
Moles= representative particles × (1 mole)/(6.02X 10^23 representative particles)
Converting Moles to Number of Particles (291-293) Ben Ross
Mole conversion involves a lot of math.
One example of this conversion is Carbon Dioxide, which is composed of three atoms.
This is dimensional analysis.
Moles.
Ben Ross
The Mass of a Mole of an Element (293-294)
Delia Calderon
Average carbon atom (atomic mass of 12 amu) is twelve times heavier than average hydrogen atom
12.0 g of carbon atom and 1.0 g of hydrogen atoms contain the same number of atoms. The mass ratio of 12 carbon atoms to 1 hydrogen atom remains the same no matter what unit is used to express it.
each element. {Atomic_mass.jpg}
{Atomic_mass.jpg}
The atomic mass of an elementexpressed in grams is the mass of a mole of the element.
The mass of a mole of an element is its molar mass.
The molar mass of any element contains 1 mol or 6.02 x 1023 atoms of that element.
Molar mass is the mass of 1 mol of atoms of any element.
By: Delia Calderon
The Mass of a Mole of a Compound (295-296)
Elaney Marcotte
10.2: Mole-Mass and Mole Volume
The Mole-Mass Relationship (297-300)
Katie West and Marissa Chura (Put your names right before your separate entries)
ConvertingConverting Moles to Mass- MarissaMass
Marissa Chura
Problem: What is the mass of 9.45 mol of aluminum oxide?
Step One: Analyze
The formula for molar mass is as follows:
Mass(grams) = number of moles x mass(grams)/1 mole
to Moles - Kati
Kati West
Problem: Rust is iron (III) oxide, of Fe2O3. How many moles of iron (III) oxide are contained in 92.2g of Fe2O3
Step 1: Analyze

Measuring Matter (287-288)
Brendan Morrisey
There are a number of ways in which you can measure matter
You can often measure the amount of something by one of three different methods--by count, mass, and volume
Some of the units used for measuring indicate a specific number of items, ex. a pair = two and a dozen = 12
Apples can be measured in these three different ways
Each of these ways can be equated to a dozen apples
By count: 1 dozen apples=12 apples
(For average-sized apples) By mass: 1 dozen apples=2.0kg
(For average-sized apples) By volume: 1 dozen apples=0.20 bushel apples
Knowing how the count, mass, and volume of apples relate to a dozen apples allows you to convert among these units
Based on the unit relationships given above, you can calculate the mass of a bushel of apples or the mass of 90 average-sized apples using conversion factors such as:
1 dozen htmldiff1apples:12 apples
2.0 kg htmldiff2apples:1 dozen apples
1 dozen htmldiff3apples: 0.20 bushel apples
Finding Mass from a Count (289) Dan Lynch
In this section you learn how to find the mass of a sum of objects.

Practice Problems
Frank "the Tank" Morley
Calculate the volume:
assume these are all the moles of gaseous elements: 1 mole fills 22.4 L at STP
.375 moles
.780 moles
.60 moles
.75 moles
,85 moles
.450 moles
50 moles
7.5 moles
9.2 moles
7.8 moles
122 moles
12.25 moles
10.75 moles
60.7 moles
1.1 moles
.123 moles
Calculate mass:
All gaseous elements occupy 22.4 L. assume all are densities of gaseous elemnts
1.256g/L
24g/L
30g/L
36.6g/L
1.67g/L
2.7g/L
3.8g/L
9.75g/L
9.789g/L
67g/L
88g/L
10.3: Percent Composition and Chemical Formulas
The Percent Composition of a Compound (305-306)