I.M.S. SCIENCE    MR. SCHAEFERS    NAME(s): ______________ _____________________

                                               PERIOD: ____ DATE: _______ SCORE: ____/20

KEEP EYE DROPPERS 1 CM. ABOVE !

MOLE-  (6.02 X 10^ 23)

Molar solution (Moles/Liter) is a ratio number of moles of a substance ( called solute )

      placed in enough water(called solvent)so that the total volume is one liter.

 

The molecular weight (also called the formula weight and molar mass)

 

of Na OH is 40 grams ( Na: 23 + O: 16 + H : 1 = 40 grams )

 

So to make a .5 L of a .3 M ( .3 M * .5 L = .15   ) solution of:

 

Example: ). NaOH                          = 40 grams * .15 =  6  grams

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1) K I             = K   +  I             = __ grams * .15 = ___ grams

 

2) Na2 ( C O 3 )   = Na2  + C 1  + O 3      = __ grams * .15 = ___ grams

 

3) Pb( N O 3 )2    = Pb    + N 2  + O 6     = __ grams * .15 = ___ grams

 

4) Cu( N O 3 )2    = Cu    + N 2  + O 6     = __ grams * .15 = ___ grams

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cations & anions:

 

K+ I-,  Na  OH ,  Na2  ( C O 3 )  , Pb  ( N O 3 )2 , Cu  ( N O 3 )2

 

      A X    +  C  Y    ======> A   Y  +  C   X

 

      A+ B-  +  C+ D-   ======> A+  D- +  C+  B-

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A TABLESPOON OF WATER - COUNT 1 MOLECULE PER SECOND= 8 X 10 ^ 6 YEARS

 

- AMOUNT BASED ON C-12 ,12 GRAMS = AVOGADRO’S NUMBER = 6.02 X 10 ^23 *See below

 

- MASS OF A SUBSTANCE (6.02 X 10^ 23) IS CALLED A MOLE

 

- NUMERICAL PART = ATOMIC WEIGHT

      SO H = 1 GRAM : C = 12 GRAMS  12: 1 RATIO OF ATOMIC WEIGHTS

 

- 5 MOLES OF OXYGEN = 5 X 16 GRAMS = 80 GRAMS OF OXYGEN

 

- 5 MOLES OF SULFUR = 5 X 32 GRAMS = 160 GRAMS OF SULFUR

 

      SO    80 G/ 160 G = 1/2

 

- IF THE QUANTITIES OF THE TWO ELEMENTS ARE IN THE SAME RATIO AS THEIR ATOMIC WEIGHTS
  THEY CONTAIN THE SAME NUMBER OF ATOMS.

 

- MASS OF MOLECULAR SUBSTANCE IN GRAMS IS EQUAL TO ITS MOLECULAR WEIGHT, ITS GRAM
 MOLECULAR WEIGHT / COVALENT BONDS

 

- GM  MOLECULAR WEIGHT OF A DIATOMIC MOLECULAR ELEMENT IS ONE MOLE  O2  H2   CL2

 

- GM  MOLECULAR WEIGHT OF A MOLECULAR SUBSTANCE IS ONE MOLE OF MOLECULES OF THE
  
  SUBSTANCE.   EXAMPLE: H2O  = 18 GRAMS  CH4= 16 GRAMS

- GM MOLECULAR WEIGHT OF NACL = 58.5 GRAMS, THIS IS A MOLE OF THIS COMPOUND.

 

A PRECIPITATE IS :_______________________________________________________________

I.M.S. SCIENCE    MR. SCHAEFERS    NAME(s): ______________ _____________________

MOLE-  (6.02 X 10^ 23)                         PERIOD: ____ DATE: _______ SCORE: ____/20

Definition:
1 mole of a substance is an amount equal to its molecular weight in grams. Avogadro’s number is the number of molecules in a mole of any substance, and equals (6.02 X 10^ 23). At standard temperature and pressure (STP), 1 mole of any gas occupies 22.414 liters of volume.

 

Amadeo Avogadro (1776-1856) was an Italian physicist who sought to reconcile findings by Dalton and Gay-Lussac and proposed that, at equal temperatures and pressures, equal volumes of gases have the same number of molecules.
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   Zinc          Iron             Copper         Aluminum    

   Mass= 65.4 g   Mass= 55.8 g    Mass= 63.5 g   Mass=  27g       

A=________________ B=_______________ C= _______________ D=____________
    
              

1. Determine the Identity of the element by its mass.(Do a teacher Check)  

 

Mass=__________g   Mass=__________g   Mass=_________g    Mass=__________g

2. Calculate the mass of an Al atom.     Calculate the mass of an Zn atom.

Solution:

 

27.0 g =  27.0 g  = ______ X 10^-23g   ____ g =     .0 g = _____ X 10^-23g              1 mole  6.02 X 10^23                  1 mole  6.02 X 10^2
       Avogadro’s number                    Avogadro’s number

 

3.  Calculate the volume of an Aluminum atom. Assume Al atom is cube shaped.

Volume Al atom =(1.27 cm X1.27 cm X ____ cm)/(6.02 X 10^ -23)= _______cm^3

Volume Cu atom =(1.27 cm X1.27 cm X ____ cm)/(6.02 X 10^ -23)= _______cm^3


Volume Zinc atom =(1.27 cm X1.27 cm X ____ cm)/(6.02 X 10^ -23)=______cm^3

Volume Iron atom =(1.27 cm X1.27 cm X ____ cm)/(6.02 X 10^ -23)=______cm^3 

4. Calculate the “diameter” of an Al atom
                   = (volume of cube just able to contain Al atom)^ 1/3

                          (1.6 X 10^-23)^1/3  =  _________ X 10^-8 cm.

So: the “radius” of Al atom =
             (“diameter” of  Al atom/ 2)=_______X 10^-8
cm.                     
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