The Mole Concept: 

Read the essay by Amedeo Avogadro (1811) W on a manner of determining
the relative masses of the elementary molecules.
A
Mole Is:
 6.02 x 10^{23} of anything.
 The formula mass in grams of a substance contains one mole of
particles.
 N_{a} = Avogadroës Number = 6.02
x 10^{23}
 

The mole is important because:
 It allows us to weigh atoms in the lab.
 It allows us to compare amounts of atoms in chemical reactions.


Basic mole calculations: convert mass to moles, and
moles to molecules or atoms.

The following equalities are used in mole calculations:
 1 mole = 6.02 x 10^{23} atoms
or molecules = formula mass in grams
Examples of Mole Conversion Problems:
These problems are set up correctly using Factor Label. Use a
calculator to find each answer with the proper number of significant
digits.
 Given 12.011 grams of carbon, how many atoms do you have?
 Given 18 grams of water, how many molecules do you have?
 Given 3.5 moles of sodium chloride, how many grams do you
have?
 What is the mass of 6.02 x 10^{23} molecules of silver
nitrate?
 

Setting up the factorlabel problem is just as important as the answer.
Form the habit of working neatly, canceling units, and circling the
answer.
Remember, units are just as important as numbers in the answer. 
