# molarconv_pres

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```					Ch. 10 – The Mole

I. Molar Conversions

I    II   III   IV
A. What is the Mole?

   A counting number (like a dozen)

   1 mole = 6.022  1023 representative
particles
A. What is the Mole?

   1 mole of eggs would fill all the
oceans on Earth…more than 30
million times!
   1 mole of basketballs would fill a
bag the size of the earth!

   1 mole of pennies would cover
the Earth ¼ mile deep!
B. Mole/Particle Conversions
6.022  1023
NA
NUMBER
MOLES                          OF
PARTICLES

(particles/mol)      Particles =
NA atoms/mol          atoms,
molecules,
NA molecules/mol   formula units,
ions, etc
B. Mole/Particle Conversion Examples

 How many molecules are in
2.50 moles of C12H22O11?

2.50 mol    6.02  1023
molecules
C12H22O11
C12H22O11
= 1.51  1024
1 mol
C12H22O11     molecules
C12H22O11
B. Mole/Particle Conversion Examples

 Ifyou have 2.23 x 1018 atoms of
sodium, how many moles is
that?

2.23  1018 1 mole Na
atoms Na                   3.70 x 10-6
6.02  1023   = moles Na
atoms Na
B. Mole/Particle Conversion Examples

 How many formula units is 3.75
moles of calcium hydroxide?

6.02  1023
3.75    formula units
mol Ca(OH)2 Ca(OH)2
= 2.26  1024
1 mol Ca(OH)2 formula units
Ca(OH)2
C. Molar Mass
relationship between number of
particles and volume of a gas
   This was used to find the
relationship for particles in a mole
Representative Particles & Moles

Substance Chemical Representative Rep Particles
Formula     Particle    in 1.00 mole
Carbon       C        Atom         6.02 x 1023

Nitrogen
gas
N2      Molecule      6.02 x 1023

Calcium ion   Ca2+       Ion         6.02 x 1023

Magnesium
fluoride
MgF2   Formula unit    6.02 x 1023
C. Molar Mass
   Mass of 1 mole of an element or
compound

   Atomic mass (on the PT) tells the...
 mass of each atom (amu)
 grams per mole (g/mol)
   Round to 2 decimal places
C. Molar Mass Examples

   carbon     12.01 g/mol

   aluminum   26.98 g/mol

   zinc       65.39 g/mol
C. Molar Mass Examples

   water
 H2O
 2(1.01) + 16.00 = 18.02 g/mol

   sodium chloride
 NaCl
 22.99 + 35.45 = 58.44 g/mol
C. Molar Mass Examples

   sodium bicarbonate
 NaHCO3
 22.99 + 1.01 + 12.01 + 3(16.00)
= 84.01 g/mol
   sucrose
 C12H22O11
 12(12.01) + 22(1.01) + 11(16.00)
= 342.34 g/mol
C. Molar Mass Examples

   magnesium hydroxide
 Mg(OH)2
 24.31 + 2(16.00) + 2(1.01)
= 58.33 g/mol
 ammonium sulfate
 (NH4)2SO4
 2(14.01) + 8(1.01) + 32.06 +
4(16.00)       = 132.16 g/mol
D. Molar Conversions

molar             6.02  1023
mass                  NA
MASS                                          NUMBER
IN               MOLES                           OF
GRAMS                                       PARTICLES
(g/mol)           (particles/mol)
Particles = atoms,
molecules, formula
units, ions, etc
NA atoms/mol

NA molecules/mol
D. Molar Conversion Examples
 Howmany moles of carbon
atoms are in 26 g of carbon?

26 g C 1 mol C
= 2.2 mol C
12.01 g C
D. Molar Conversion Examples
 Findthe mass of 2.1  1024
molecules of NaHCO3.
2.1  1024
Molecules 1 mol         84.01 g
NaHCO3      NaHCO3       NaHCO3
6.02  1023 1 mol
Molecules     NaHCO3
NaHCO3
= 290 g NaHCO3
D. Molar Conversion Examples
 Howmany moles are in 22.5
grams of potassium?

6.02  1023
22.5 g K    1 mol K   atoms K
39.10 g K 1 mol K

= 3.46 x 1023 atoms K

```
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