```The MoleStringer, S. C.                       Morgan Park High School                                      881-5050                          Objectives:

Resolution of Problems:
The role of a unifying hypothesis (law) and the reasoning

Application of Hypothesis:
Diatomic and monoatomic gaseous elements.  Avogadro's
hypothsis.  Determination of molecular weights, atomic
weights, etc.

Fundamental Skills:
Solving problems by use of the gas constants:

D(gas) = g mol wt(g)/22.4 l

g mol wt(g) = D(gas) * 22.4 l

D(gas) = (g/ml)*(1000ml/l)

Topic Statement:

The data below will apply to Avogadro's hypothesis.  This
exercise preceded the review of the chapter on the gas laws:
Boyle's, Charles', Gay-Lussac's, indicating similarities in the
physical behavior of gases.  The question of whether gases
display any similarities in chemical behavior may then be raised.
Discussion of the experimental findings of Gay-Lussac and Proust
used to explain Gay-Lussac's Law, and the inconsistency with
Dalton's Theory may be resolved.  Also, consider the historical
treatment and significance as in the basic chapter.

The diagram of the mole concept and a work sheet follows below:

divide by 22.4 l -->| M |--> multiply by GAW/GMW
volume (l) <---------------| O |----------------------> mass (grams)
multiply by 22.4 l <--| L |<-- divide by GAW/GMW
| E |
divide by 6.02 * 1023 -->|   |--> multiply by 6.02 * 1023
|
V
number of
particles

Diatomic elements:              Define:          Br, I, N, Cl, H, O, F           Density = M/unit volume                                         Volume = L * W * H                                         Liquids = cylinder (3l)     GAW = atoms                         Gas = displacement     GMW = molecules                     Weight = grams  D =  M/V             /--- mass at 1 mole GAW/m wt.MOLE -------<---- 6.02 * 1023 particles             \--- at STP vol of 1 mole of gas = 22.4 l Substance                  Density             Volume of 1 mole
1.  Mercury               | 13.55 g/cm3    |2.  Iron                  |  7.85 g/cm3    |3.  Ethanol (C2H5OH)      |  0.80 g/ml     |4.  Propanol (C3H8OH)     |  0.78 g/ml     |5.  Carbon tetrachloride  |  1.59 g/ml     |                 etc.                            Chemistry
all of these contain 1 mole

SUBSTANCE    NUMBER OF MOLECULES  FORMULA  MASS(g)  ML ESTIMATE VOL.
Copper 8.92  |                   |        |        |   63.5/8.92 =
Aluminum 2.70|                   |        |        |   27.0/27.0 = 10.0
Iron 7.86    |                   |        |        |   55.8/7.86 =
Lead 11.34   |                   |        |        |
Zinc 7.14    |                   |        |        |
Tin 5.75     |                   |        |        |
etc.  |                   |        |        |

```