Ch. 9 The Mole

Ch. 10 The Mole

6.02 X 1023SAVE PAPER AND INK!!! When you print out the notes on PowerPoint, print "Handouts" instead of "Slides" in the print setup. Also, turn off the backgrounds (Tools>Options>Print>UNcheck "Background Printing")!

1To play the movies and simulations included, view the presentation in Slide Show Mode.

The MoleVolume Relationship10.2

61In each container, the volume occupied by the gas molecules is small compared with the containers volume, so the molecules are not tightly packed. a) The molecules in this container are small. b) This container can accommodate the same number of larger molecules.Chemical equations can be interpreted in many ways!

We will use the mole interpretation!Which interpretationssupport the Law of Conservation of Mass?Atoms & Mass!Only mass &Atoms are conserved in every reaction!3Chemical Equations are simple.2H2 + O2 2H2O

Chemical equations are quite easy. Here we count out 4 hydrogens and 2 oxygen atoms and we can make two water molecules. But how many hydrogens and oxygens would we count out to make enough water to fill a one liter bottle of water?4

Imagine the number of grains of sand in a handful of sand: thousands or maybe a million? It would be difficult to count that many. Now imagine the number of grains of sand that would be present if we covered all of the Earth (land and sea) 10 miles deep with sand. That number of grains of sands is the same number of water molecules needed to fill a 1 liter bottle!

The Art of Counting Without Counting

COUNTING COINS WITHOUT COUNTINGOne way to measure the amount of a substance available is to count the # of particles in that sampleHowever, atoms & molecules are extremely smalland, the # of individual particles in even a small sample is very largeTherefore, counting the # of particles is not a practical measure of amountTo solve this problem, scientists developed the concept of the moleIts the chemical counting unitHow Scientists Keep Track of Atoms Just as a dozen eggs equals 12 eggs, a Mole = 6.02 x 1023 602,000,000,000,000,000,000,000It is equal to that number no matter what kind of particles youre counting!It could represent donuts, pens, bikes, atoms, molecules, etc.The word mole was introduced about 1896 by Wilhelm Oswald, who derived the term from the Latin word moles meaning a heap or pile.The mole is the SI base unit for measuring the amount of a substance.Avogadros Number6.02 X 1023This number is named in honor of Amadeo Avogadro (1776 1856), who studied quantities of gases and discovered that no matter what the gas was, there were the same number of molecules presentunder certain conditions.

The Mole 1 mole of anything = 6.022 1023 units of that thing6.022 1023 is equal to the number of carbon atoms in exactly 12 grams of pure carbon-12.

Water 18.02 gCaCO3 100.09 gOxygen 32.00 gCopper 63.55 gOne mole of common substances.12

The MoleThis photograph shows one mole of solid (NaCl), liquid (H2O), and N2 gas.

Mass and Moles of a Substance

1-octanol (C8H17OH)Mercury(II) Iodide (HgI2)Methanol (CH3OH)Sulfur (S8)One mole of different substances.14141 Mole of Particles

15Exactly How Big is a Mole?Q: How long would it take to spend a mole of $1 coins if they were being spent at a rate of 1 billion per second?

Also known as: The Get-a-Life Syndrome!A MollionaireA: If a mole of $1 coins were being spent at a rate of 1 billion per second: $ 6.02 x 1023 / $1 000 000 000 = 6.02 x 1014 payments = 6.02 x 1014 seconds6.02 x 1014 seconds / 60 = 1.003 x 1013 minutes1.003 x 1013 minutes /60 = 1.672 x 1011 hours1.672 x 1011 hours / 24 = 6.968 x 109 days6.968 x 109 days / 365.25 = 1.908 x 107 yearsA: It would take 19 million years

Just How Big is a Mole?Enough soft drink cans to cover the surface of the earth to a depth of over 200 miles. If you had Avogadro's number of unpopped popcorn kernels, and spread them across the United States of America, the country would be covered in popcorn to a depth of over 9 miles. If we were able to count atoms at the rate of 10 million per second, it would take about 2 billion years to count the atoms in one mole.

More Examples, please!One mole of marbles would cover the entire Earth (oceans included) for a depth of three miles.One mole of $100 bills stacked one on top of another would reach from the Sun to Pluto and back 7.5 milliontimes.It would take light 9500 years to travel from the bottom to the top of a stack of 1 mole of $1 bills.

206.02 x 1023 softballs = volume of Earth6.02 x 1023 Olympic shot puts = mass of Earth6.02 x 1023 atoms H laid side by side would encircle Earth ~1,000,000 times

Reminder: The Mole is just a counting number!1 dozen cookies = 12 cookies1 mole of cookies = 6.02 X 1023 cookies

1 dozen cars = 12 cars1 mole of cars = 6.02 X 1023 cars

1 dozen Al atoms = 12 Al atoms1 mole of Al atoms = 6.02 X 1023 atoms

Mole is abbreviated mol (gee, thats a lot quicker to write, huh?)

How Do We Use The Mole?We never use the mole to describe macroscopic or real world objects. 1 mole (6.02x1023) of watermelon seeds would be found inside a watermelon the size of the moon.1 mole (6.02x1023) of donut holes would cover the earth and would be 5 miles deep. Since the mole is such a huge number of items, it is only used to describe the amount of things that are very, very small.1 mole (6.02x1023) of water molecules would barely fill a shot glass

Yummm! Donuts! I love chemistry!= 6.02 x 1023 C atoms= 6.02 x 1023 H2O molecules= 6.02 x 1023 NaCl formula units(6.02 x 1023 Na+ ions and 6.02 x 1023 Cl ions)A Mole of Particles Contains 6.02 x 1023 particles 1 mole C

1 mole H2O

1 mole NaCl

The Mole

1 amu = 1.66054 x 10-24 g1 g = 6.02214 x 1023 amuSame #, different unit label!Suppose we invented a new counting unit called a Salb and one Salb contains 8 objects. 1. How many paper clips in 1 Salb?a) 1b) 4c) 82. How many oranges in 2.0 Salbs? a) 4b) 8c) 16 3. How many Salbs contain 40 gummy bears? a) 5b) 10c) 20

Learning Check 6.02 x 1023 particles 1 mole or

1 mole6.02 x 1023 particles

Note that a particle can be an atom, molecule, formula unit, or ion!

We can use Avogadros # in Conversion Factors

Oh, Goody!REPRESENTATIVE PARTICLES & MOLESATOMIC NITROGENAtomN6.02x1023NITROGEN GASMoleculeN26.02x1023WATERMoleculeH206.02x1023CALCIUM IONIonCa2+6.02x1023CALCIUM FLUORIDEFormula UnitCaF26.02x1023SUBTANCEREPRESENTATIVEPARTICLECHEMICALFORMULAREP. PARTICLEIN 1 MOLConverting Between Moles and Particles

Do you know how to measure out 3 moles of sugar or salt or water?The mole is a counting unit, so we would have to count out 6.02x1023 particles of each substance. (no thank you)There are 2 ways we can use to measure out a number of moles of a substance.Measure it in grams (a mass)Or measure it in liters (a volume) How we measure moles1. Number of atoms in 0.500 mole of Ala) 500 Al atoms b) 6.02 x 1023 Al atomsc) 3.01 x 1023 Al atoms

Learning Check

0.500 mol Al 1 mole Al6.02 x 1023 atoms Al=3.01 X 1023 atoms Al2.Number of moles of S in 1.8 x 1024 S atomsa) 1.0 mole S atomsb) 3.0 mole S atomsc) 1.1 x 1048 mole S atoms1.8 x 1024 atoms S6.02 x 1023 atoms S1 mole S=3.0 moles SLets look at Mass of ParticlesAtomic Mass: The mass of an atom (measured in amus.)Molecular Mass: the sum of atomic masses of all atoms in a molecule (measured in amus.) example: H2O has a formula mass of 18.0 a.m.uFormula Mass: Sum of the mass of atoms in a formula unit of an ionic compound (measured in amus.) example: NaCl has a formula mass of 58.5 a.m.u.

Formula mass is the sum of the atomic masses (in amu) in a formula unit of an ionic compound.Na1 x 23.0 amuCl 1 x 35.5 amu NaCl58.5 amu

NaCl= 23.0 = 35.53333Molecular mass is the sum ofthe atomic masses (in amu) in a molecule.

SO2S1 x32.1 amuO2 x 16.0 amu SO264.1 amu= 32.1= 32.03434Lets review what we already know..We already know that 1 atom of C-12 has a mass of 2.010 x 10-23 g. (This is also equal to 12 amu!)

We also want the atomic mass of 12.0 amu to become 12.0 g.

So, the problem becomes this..2.010 x 10-23 g/atom C-12 x ? atoms = 12.0 g C-12

Why not use the average atomic mass that is already on the periodic table? It is already a relative mass, right? Why reinvent the wheel?

But the atomic mass on the chart is in AMU, not grams! We do not have an AMU balance!

Then lets convert the number on the periodic chart from AMU to grams!

3939Molar MassA substances molar mass is its formula mass in grams.CO2 = 44.01 grams per moleH2O = 18.02 grams per moleCa(OH)2 = 74.10 grams per moleC = 12.0 g/moleWhat is the mass of 1 mole of C6H12O6?Calculating molar masses using chemical formulasThe overall mass of 1 mole of C6H12O6 will be the molar mass of 6 Carbons + the molar mass of 12 Hydrogens + the molar mass of 6 Oxygens.6 Carbons =12.011 g 6 *12 Hydrogens =1.0079 g 12 *= 72.066 g = 12.095 g 6 Oxygens =15.999 g 6 *= 95. 994 g 180.16 g/mole Periodic Table of the ElementsThe numbers under the element names are the relative weights. However, if you consider one mole of the element (6 x 1023 atoms) then these numbers are read as grams.

Molar massThe mass of one mole is called molar massEx. 1 mol Li = 6.94 g LiThis is expressed as 6.94 g/molWhat are the following molar masses?SSO2Cu3(BO3)232.06 g/mol64.06 g/mol308.1 g/molCalculate molar masses (to 2 decimal places) CaCl2 (NH4)2CO3 O2 Pb3(PO4)2 C6H12O6Cux 3 = 63.5 x 3= 190. 5Bx 2 = 10.8 x 2= 21.6Ox 6 = 16.0 x 6= 96.0308.1gFind the molar mass (usually we round to the tenths place)Learning Check!1 mole of Br atoms1 mole of Sn atoms=79.9 g/mole= 118.7 g/mole

Mass in grams of 1 mole equal numerically to the sum of the atomic masses1 mole of CaCl2 = 111.1 g/mol 1 mole Ca x 40.1 g/mol + 2 moles Cl x 35.5 g/mol = 111.1 g/mol CaCl21 mole of N2O4 = 92.0 g/mol Molar Mass of Molecules and Compounds

Molar Mass of K2O = ? Grams/mole

B. Molar Mass of antacid Al(OH)3 = ? Grams/moleLearning Check!

Prozac, C17H18F3NO, is a widely used antidepressant that inhibits the uptake of serotonin by the brain. Find its molar mass.Learning Check

molar mass Grams Moles

Calculations with Molar Mass

Converting between grams and molesIf we are given the # of grams of a compound we can determine the # of moles, & vise-versaIn order to convert from one to the other you must first calculate molar massg = mol given gfm mol = g given 1 mol 1 mole gfm0.25HCl53.15H2SO43.55NaCl1.27Cumol (n)massgfmFormula9.136.460.541998.0820758.440.020063.55Converting between Grams and MolesUSE MOLAR MASS as your conversion factor!

51These aluminum satellite dishes at the National Radio Astronomy Observatory near Soccoro, New Mexico are naturally protected from corrosion by the formation of a thin film of aluminum oxide (Al2O3).

53Rust weakens an iron chain.

Aluminum is often used for the structure of light-weight bicycle frames. How many grams of Al are in 3.00 moles of Al?3.00 moles Al ? g Al

Converting Moles and Grams

1. Molar mass of Al1 mole Al = 27.0 g Al2. Conversion factors for Al 27.0g Al or 1 mol Al 1 mol Al 27.0 g Al

3. Setup3.00 moles Al x 27.0 g Al 1 mole AlAnswer = 81.0 g Al

The artificial sweetener aspartame (Nutra-Sweet) formula C14H18N2O5 is used to sweeten diet foods, coffee and soft drinks. How many moles of aspartame are present in 225 g of aspartame?

Learning Check!

COUNTING ATOMS IN GASESStandard Molar Volume

Equal volumes of all gases at the same temperature and pressure contain the same number of molecules. - Amadeo AvogadroAt STP (Standard Temperature and Pressure): 1 mole of a gas occupies 22.4 liters of volumeConvert Between Moles and Volume

ExamplesWhat is the volume of 4.59 mole of CO2 gas at STP?62Atoms/Molecules and GramsSince 6.02 X 1023 particles = 1 mole AND1 mole = molar mass (grams)You can convert atoms/molecules to moles and then moles to grams! (Two step process)You cant go directly from atoms to grams!!!! You MUST go thru MOLES.Thats like asking 2 dozen cookies weigh how many ounces if 1 cookie weighs 4 oz? You have to convert to dozen first!

molar mass Avogadros number Grams Moles particles

Everything must go through Moles!!!Calculations

volume22.4 LAll Conversions So Far TOGETHER

Interconverting Moles, Mass, and Number of Chemical EntitiesMass (g) = no. of moles x no. of grams1 molNo. of moles = mass (g) xno. of grams1 molNo. of particles = no. of moles x6.022x1023 particles1 molNo. of moles = no. of particles x 6.022x1023 particles1 mol66Atoms/Molecules and GramsHow many atoms of Cu are present in 35.4 g of Cu?35.4 g Cu 1 mol Cu 6.02 X 1023 atoms Cu 63.5 g Cu 1 mol Cu= 3.36 X 1023 atoms Cu

Learning Check!How many atoms of K are present in 78.4 g of K?

Learning Check!What is the mass (in grams) of 1.20 X 1024 molecules of glucose (C6H12O6)?

Learning Check!How many atoms of O are present in 78.1 g of oxygen?78.1 g O2 1 mol O2 6.02 X 1023 molecules O2 2 atoms O 32.0 g O2 1 mol O2 1 molecule O2

2.94 x 1024HINTS: If you see atoms, molecules, formula units, or ions, you will use Avogadros numberIf you see liters, you will use Molar Volume (22.4L)If you see grams, you will use Molar Mass (gfm)

Density and the MoleIf we know the density of a gas, we can use it to calculate its GFM.Remember: Density = mass/volume

Ex. Lets say we know the density of a gas is 1.964 g/L, and we know it consists of C & O.We dont, however, know if it is CO or CO2.1st Convert Liters to moles: density 22.4L 1.964 g 22.4 L 1 L 1 mole

2nd Compare to the GFM of CO & CO2Whats the compound? CO2 = 44.0 g/mole28 g/mole & 44 g/mole1 L 1 mole

Density & Moles, Cont.Ex. The densities of gases A, B, & C are1.25, 2.86, & .714 g/L, respectively. calculate the GFM for each. Then, identify each substance as NH3, SO2, Cl2, N2, or CH4.

(multiply each density by 22.4L/1 mole)Density & Moles, Cont.If you are given the formula of a gas, you can find its density at STP.

GFM 1 mole1 mole 22.4 L

Whats the density of CO gas at STP? 28 g 1 mole 1 mole 22.4 L = 1.25 g/LPercent compositionThe percent by mass of each element in a sample of a compound

To determine % composition from a formula

Percent CompositionLike all percents Part divided by the Whole x 100 %Find the mass of each component,divide by the total mass.Multiply by 100Mass % of element X = (atoms of X in formula) x (atomic mass of X)formula mass of compoundx 100Mass percent from the chemical formula77What is the percent carbon in C5H8NO4 (the glutamic acid used to make MSG monosodium glutamate), a compound used to flavor foods and tenderize meats?a) 8.22 %Cb) 24.3 %Cc) 41.1 %C

Percent Composition

Find the gfm of the compound:

C 5 x 12.0 = 60.0H 8 x 1.0 = 8.0N 1 x 14.0 = 14.0O 4 x 16.0 = 64.0

146.02. Part/Whole x 100

60.0 146.0 X 100 = 41.1 % Carbon by massSimplest and molecular formulasConsider NaCl (ionic) vs. H2O2 (covalent) Cl Na Na Cl Cl Cl Na NaChemical formulas are either simplest (a.k.a. empirical) or molecular. Ionic compounds are always expressed as simplest formulas.Covalent compounds can either be molecular formulas (I.e. H2O2) or simplest (e.g. HO)Q - Write simplest formulas for propene (C3H6), C2H2, glucose (C6H12O6), octane (C8H14)Q - Identify these as simplest formula, molecularformula, or both H2O, C4H10, CH, NaCl HOO H HOO H HOO HAnswersQ - Write simplest formulas for propene (C3H6), C2H2, glucose (C6H12O6), octane (C8H14)Q - Identify these as simplest formula, molecularformula, or both H2O, C4H10, CH, NaClA - CH2A - H2O is both simplest and molecularC4H10 is molecular (C2H5 would be simplest)CH is simplest (not molecular since CH cant form a molecule - recall Lewis diagrams)NaCl is simplest (its ionic, thus it doesnt form molecules; it has no molecular formula)CHCH2OC4H7For more lessons, visit www.chalkbored.comTypes of Formulas

Empirical FormulaThe formula of a compound that expresses the smallest whole number ratio of the atoms present.Formula Units for ionic compounds are always empirical (lowest whole number ratio).Examples:NaCl MgCl2 Al2(SO4)3 K2CO3Molecular Formula - shows the actual number of each kind of atom found in one molecule of the compound.Examples: C6H12O6 N2O4Empirical FormulasEthyne (C2H2) is a gas used in welders torches. Styrene (C8H8) is used in making polystyrene. These two hydrocarbons have the same empirical formula (CH) but different molecular formulas.10.3

83Ethyne (C2H2), also called acetylene, is a gas used in welders torches. Styrene (C8H8) is used in making polystyrene. These two compounds have the same empirical formula. Calculating What is the empirical formula of ethyne and styrene?Formulas (continued)Formulas for molecular compounds MIGHT be empirical (lowest whole number ratio).Molecular:H2OC6H12O6C12H22O11Empirical:H2OCH2O C12H22O11Formulas of Compounds

Formulas give the relative numbers of atoms or moles of each element in a formula unit - always a whole number ratio (the law of definite proportions).

NO2 2 atoms of O for every 1 atom of N 1 mole of NO2 : 2 moles of O atoms to every 1 mole of N atoms

If we know or can determine the relative number of moles of each element in a compound, we can determine a formula for the compound.

86Finding an Empirical Formula1.Determine the mass in grams of each element present.2.Convert mass to moles for each element.3.Divide each # of moles by the smallest number of moles to obtain the simplest whole number ratio.If whole numbers are not obtained* in step 3), multiply each by the smallest number that will give all whole numbers* Be careful! Do not round off numbers prematurelyEmpirical Formula CalculationsQ- a compound is found to contain the following % by mass: 69.58% Ba, 6.090% C, 24.32% O. What is the empirical formula?Step 1: Convert each mass to moles. (calculate the # of moles (mol = g x mol/gfm) of each element.)Step 2: Divide each answer from step 1 by the lowest number of moles (to get simplestwhole # ratio)Step 3: Use the #s from step 2 as subscripts.(Make sure the elements are in the correct order!)88Simplest formula: sample problemQ- 69.58% Ba, 6.090% C, 24.32% O.What is the empirical formula?1: 69.58 g Ba, 6.090 g C, 24.32 g O2: Ba:69.58 g x 1 mol/ 137.3g = 0.507 mol BaC: 6.090 g x 1 mol/ 12.0g = 0.508 mol CO: 24.32 g x 1 mol/ 16.0g = 1.52 mol O3: 4: the simplest formula is BaCO3 (1:1:3 ratio)mol (reduced)mol1.52/ 0.507 = 3.0000.508/ 0.507 = 1.0020.507/ 0.507 = 1.0001.520.5080.507OCBa89Mole ratios and simplest formula Given the following mole ratios for the hypothetical compound AxBy, what would x and y be if the mol ratio of A and B were:A = 1 mol, B = 2.98 molA = 1.337 mol, B = 1 molA = 2.34 mol, B = 1 molA = 1 mol, B = 1.48 molAB3A4B3A7B3A2B390Ex. A compound consists of 29.1 % Na, 40.5 % S, and 30.4 % O. Determine the empirical formula.1: Assume 100 g: 29.1 g Na, 40.5 g S, 30.4 g O2: Na: 29.1 g x 1 mol/ 23.0 g = 1.27 mol Na S: 40.5 g x 1 mol/ 32.1 g = 1.26 mol S O: 30.4 g x1 mol/ 16.0 g = 1.90 mol Omol (reduced)X 2mol1.90/ 1.26 = 1.5131.26/ 1.26 = 1.0021.27/ 1.26 = 1.0121.901.261.27OSNa4: the simplest formula is Na2S2O3A sample of a brown gas, a major air pollutant, is found to contain 2.34 g N and 5.34g O. Determine a formula for this substance.Convert grams to moles

moles N = 2.34g N 1 mole N = 0.167 moles N 14.0 g N

moles O = 5.34g O 1mole O = 0.334 moles O 16.00 g O Formula cant be:

So, divide each # moles by the smallest one!

A compound is composed of 7.20 g carbon,1.20 g hydrogen, and 9.60 g oxygen. Find the empirical formula for this compound.1: 7.20 g C, 1.20 g H, 9.60 g O2: C: 7.20 g x 1 mol/12.0g= 0.600 mol C H: 1.20 g x 1 mol/1.00g = 1.20 mol HO: 9.6 g x 1 mol/16.0g = 0.600 mol O3: 4: the simplest formula is CH2Omol (reduced)mol0.60/ 0.60 = 11.20/ 0.60 = 20.60/ 0.60 = 10.6001.200.600OHC93Finding Molecular formulasThere is one additional step to solving for the true molecular formula of a compound. First you must be given the molar mass of the compound. (ex. 150 g/mole)1. Determine molar mass of the empirical formula. For CH2O it is 30 g/mol (12+2+16).2. Divide the molar mass of the compound by this to get a factor: 150 / 30 = 53. Multiply each subscript in the formula by this factor: C5H10O5 is the molecular formula. Q- For OF, give the molecular formula if the compound is 70 g/mol70 35 = 2 O2F294Finding the Molecular FormulaThe empirical formula for adipic acid is C3H5O2. The molecular mass of adipic acid is 146 g/mol. What is the molecular formula of adipic acid?1. Find the empirical mass of C3H5O2 3(12.0 g) + 5(1.0) + 2(16.0) = 73.0 gFinding the Molecular FormulaThe empirical formula for adipic acid is C3H5O2. The molecular mass of adipic acid is 146 g/mol. What is the molecular formula of adipic acid?3(12.0 g) + 5(1.0) + 2(16.0) = 73.0 g2. Divide the molecular mass by the emipirical mass.

Finding the Molecular FormulaThe empirical formula for adipic acid is C3H5O2. The molecular mass of adipic acid is 146 g/mol. What is the molecular formula of adipic acid?3(12.01 g) + 5(1.01) + 2(16.00) = 73.08 g

3. Multiply the empirical formula by this number to get the molecular formula.(C3H5O2) x 2 = C6H10O4Calculate the percentage composition of each substance: a) SiH4, b) FeSO4Calculate the simplest formulas for the compounds whose compositions are listed:a) carbon, 15.8%; sulfur, 84.2%b) silver,70.1%; nitrogen,9.1%; oxygen,20.8%c) K, 26.6%; Cr, 35.4%, O, 38.0%The simplest formula for glucose is CH2O and its molar mass is 180 g/mol. What is its molecular formula?Practice Problems98Determine the molecular formula for each compound below from the information listed. substancesimplest formula molar mass(g/mol) a) octaneC4H9114 b)ethanolC2H6O46 c)naphthaleneC5H4128 d)melamineCH2N2126The percentage composition and approximate molar masses of some compounds are listed below. Calculate the molecular formula of each percentage compositionmolar mass(g/mol)64.9% C, 13.5% H, 21.6% O7439.9% C, 6.7% H, 53.4 % O6040.3% B, 52.2% N, 7.5% H80991a) Si= 87.43% (28.09/32.13 x 100), H= 12.57%b) Fe= 36.77% (55.85/151.91 x 100), S= 21.10% (32.06/151.91 x 100), O= 42.13%2a) Assume 100 g. Thus: 15.8 g C, 84.2 g S.C: 15.8 g 12.01 g/mol = 1.315 mol C S: 84.2 g 32.06 g/mol= 2.626 mol Sthe simplest formula is CS22.626/1.315= 2.001.315/1.315= 1Mol reduced2.6261.315MolSC1002b)Ag:70.1 g107.87 g/mol= 0.6499 mol Ag N: 9.1 g14.01 g/mol= 0.6495 mol NO:20.8 g16.00 g/mol= 1.30 mol O.6499/.6495= 1.00.6499Ag1.30/.6495= 2.00.6495/.6495= 1Mol reduced1.300.6495MolONAgNO22c)K:26.6 g39.10 g/mol= 0.6803 mol K Cr: 35.4 g52.00 g/mol= 0.6808 mol CrO:38.0 g16.00 g/mol= 2.375 mol O.6803/.6803= 10.6803K2.375/.6495= 3.49.6808/.6803= 1.00Mol reduced2.3750.6808MolOCrK2Cr2O71013 C6H12O6 (CH2O = 30 g/mol, 180/30 = 6)4a)C8H18 (C4H9 = 57 g/mol, 114/57 = 2)b)C2H6O (C2H6O = 46 g/mol, 46/46 = 1)c)C10H8(C5H4 = 64 g/mol, 128/64 = 2)d)C3H6N6(CH2N2 = 54 g/mol, 126/42 = 3)5a)C:64.9 g12.01 g/mol= 5.404 mol C H: 13.5 g1.01 g/mol= 13.37 mol HO:21.6 g16.00 g/mol= 1.35 mol O5.404/1.35= 4.005.404C1.35/1.35= 113.37/1.35= 9.90Mol reduced1.3513.37MolOHC4H10OC4H10O (C4H10O = 74 g/mol, 74/74 = 1)1025b)C:39.9 g12.01 g/mol= 3.322 mol C H: 6.7 g1.01 g/mol= 6.63 mol HO:53.4 g16.00 g/mol= 3.338 mol O3.322/3.322= 13.322C3.338/3.322= 1.006.63/3.322= 2.0Mol reduced3.3386.63MolOHCH2OC2H4O2 (CH2O = 30 g/mol, 60/30 = 2)5c)3.728/3.726= 1.003.728B7.43/3.726= 2.03.726/3.726= 1Mol reduced7.433.726MolHNB3N3H6 (BNH2 = 26.84 g/mol, 80/26.84= 2.98)For more lessons, visit www.chalkbored.com103atomic1 molemass1 moleatomicmassMass1 mole22.4 L1 mole22.4 LRepresentativeParticlesVolume of Gasat STP6.02x10231 mole1 mole6.02x1023Moleatomic1 molemass1 moleatomicmassMass1 mole22.4 L1 mole22.4 LRepresentativeParticlesVolume of Gasat STP6.02x10231 mole1 mole6.02x1023MoleVolumeIonsAtomsRepresentative ParticlesMassPTMoles6.02 x 1023 22.4 LCount 105Comparing sugar (C12H22O11) & H2ONo, sugar has more (45:3 ratio)Yes (6.02 x 1023 in each)Yes.No, molecules have dif. massesNo, molecules have dif. sizes.1 mol eachYes, thats what grams are.mass?No, they have dif. molar masses# of moles?No, they have dif. molar masses# of molecules?No# of atoms?No, they have dif. densities.volume?1 gram eachSameThe Molar Mass and Number of Particles in One-Mole Quantities SubstanceMolar MassNumber of Particles in One MoleCarbon (C) 12.0 g 6.02 x 1023 C atoms

Sodium (Na) 23.0 g 6.02 x 1023 Na atoms

Iron (Fe) 55.9 g 6.02 x 1023 Fe atoms

NaF (preventative 42.0 g 6.02 x 1023 NaF formula unitsfor dental cavities)

CaCO3 (antacid) 100.1 g 6.02 x 1023 CaCO3 formula units

C6H12O6 (glucose) 180.0 g 6.02 x 1023 glucose molecules

C8H10N4O2 (caffeine) 194.0 g 6.02 x 1023 caffeine molecules107 Information Contained in the Chemical Formula of Glucose C6H12O6 ( M = 180.16 g/mol)Oxygen (O)Mass/mole of compound6 atoms96.00 gCarbon (C)Hydrogen (H)Atoms/moleculeof compoundMoles of atoms/mole of compoundAtoms/mole ofcompoundMass/moleculeof compound6 atoms12 atoms6 moles of atoms12 moles of atoms 6 moles of atoms 6(6.022 x 1023) atoms 12(6.022 x 1023) atoms 6(6.022 x 1023) atoms6(12.01 amu) =72.06 amu12(1.008 amu) =12.10 amu6(16.00 amu) =96.00 amu72.06 g12.10 g1086.02 x 1023 somethings = 1

109109