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Thursday, March 8

  1. page The Mole edited ... 10: The Mole Editor: MoleEditor: Kerry Demond There DemondThere are many The mole is s…
    ...
    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.pdf
    A 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
    (view changes)
    6:35 pm
  2. page The Mole edited ... 10: The MoleEditor: Mole Editor: Kerry DemondThere Demond There are many The mole is s…
    ...
    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.
    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:
    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

    (view changes)
    6:19 pm
  3. page The Mole edited Chapter Chapter 10: The Mole Editor: MoleEditor: Kerry Demond There DemondThere are many …
    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
    (view changes)
    6:17 pm
  4. page The Mole edited Chapter Chapter 10: The Mole Editor: Editor: Kerry DemondHey guys, wiki is due THURSDAY, …
    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)
    Converting
    Converting 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
    (view changes)
    6:02 pm
  5. page The Mole edited ... Measuring Matter (287-288) Brendan Morrisey There are a number of ways in which you can mea…
    ...
    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.
    (view changes)
    5:24 pm
  6. page The Mole edited ... Practice Problems Frank "the Tank" Morley Calculate the volume: assume these are…
    ...
    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)
    (view changes)
    5:00 pm

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