41.2: Introduction
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There is a relationship between moles, grams, and the number of molecules that is similar to the relationship between dozens, grams, and the number of pieces. One mole of any substance has the same number of particles (6×1023), just as one dozen of any item has the same number of pieces (12).
Substance |
Molecules |
---|---|
1 mole H2O |
6×1023 |
1 mole CO |
6×1023 |
1 mole H |
6×1023 |
1 mole O3 |
6×1023 |
Item |
Pieces |
1 dozen Cookies |
12 |
1 dozen Roses |
12 |
1 dozen Eggs |
12 |
1 dozen Paperclips |
12 |
The mole is central to stoichiometry like the meter is central to the metric system. If the number of moles are known, then the amount of grams and the number of particles may be calculated. The atomic mass on the periodic table indicates the amount of grams that one mole of a particular type of atom would contain. Avogadro’s number is the number of atoms or molecules that 1 mole of any substance would contain.
|
NA=6×1023 particles1 mole |
1 mole of Carbon has 12.011 grams |
1 mole of Carbon has 6×1023 atoms |