The Mole by yurtgc548

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									THE MOLE
You should be able to:

Convert between molecular weight, number of
atoms, number of moles, or mass

Determine % composition of an atom
What is a mole
   A mole is a counting unit like:
     12 eggs = a dozen eggs
     60 sec = a min

     500 sheets of paper = ream
What is a mole
   Moles count particles
     6.022 x 1023 particles = a mole (mol)
     Called avagadro’s number (# atoms in 12 g 12C)

     1 mol marbles would cover earth 50 mi deep!


                                         1 mole of Cu,
                                         Al, S, K2Cr2O7,
                                         H2O and
                                         CuCl2
What is a mole
   Uses
     To count number of particles in a sample (from mass)
     Since 12 g 12C = 6.022 x 1023 atoms
       12.01   g sample of natural carbon = 6.022 x 1023 atoms
        (12C, 13C, and 14C)
     Help   use in determining outcome of reactions
practice
   How many atoms of Ar = 7.5 mol ?
     D.A.   ?: 7.5 mol = ? Atoms Ar
practice

   How many mols are in 10.0 g of Al?
     D.A.   ?: 10g Al= ? Mols Al




    How many atoms?
     D.A. ?: 0.371 moles = ? Atoms
Molar mass
   A chemical compound = collection of atoms
   Ex CO2
   Calculate the mass of 1 mol of CO2
   Think about it: mass of 1 mol of CO2 = mass of 1
    mol C + 2 mols of O
     Mass of 1 mol of C = 12.01g and
     Mass of 2 mols of O= 2 x 16.00 g
     Mass of 1 mol of CO2 = 12.01 g + 2 (16.00 g)
     =44.01 g = MOLAR MASS of CO2 (mass of 1 mole of
      CO2)
Molar Mass
   Calculate the molar mass of CH4
    =   12.01g + 4(1.008 g) = 16.04 g
   Calculate how many moles are in 1.56 x 10-2 g of
    C10H6O3
     Think  about it
     First need molar mass then do DA to solve

     =8.96 x 10-5 mol C10H6O3
        % composition
   Tells us % mass of an individual atom in a molecule
   % comp.= mass of element in 1 mol of molecule x 100%
                      mass of 1 mol of molecule
   % comp. of H in H2O
     Mass of H= 2 mol (1.008 g) = 2.016 g
     Mass of 0= 1 mol (16.00 g) = 16.00 g

 Mass of 1 mol H2O = 2.016 g + 16.00 g = 18.016 g
 % composition of H=mass of H in 1 mol of H2O x 100 %

                         mass of 1 mol of H2O
= 2.016g x 100 % = 11.2 %
  18.016g

								
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