# 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
 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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