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The Mole Concept. infinitesimally. Atoms are so _____________________ small, that. a tiny teaspoon of carbon contains an ____________________ large quantity of carbon atoms. . Unimaginably. 2.0 x 10 22. ≈. 1 tsp. charcoal. Carbon Atoms.
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infinitesimally Atoms are so _____________________ small, that a tiny teaspoon of carbon contains an ____________________large quantity of carbon atoms. Unimaginably 2.0 x 1022 ≈ 1 tsp. charcoal Carbon Atoms
The time required to count SO MANY particles is _______________long. impossibly If the time taken to count 10 atoms was 1 second. It would take 6.3 x 1013 years to count the amount of carbon atoms on the teaspoon! It is better therefore to regard particles in groups rather than individual units.
Chemists count atoms in a bulk unit called the __________. • A __________ is equivalent to the number of C-12 atoms in exactly 12 grams of C-12. mole mole 1 mol C-12 = 6.022 x 1023C-12 atoms 1 mol C-12 = 12 grams C-12 12 grams C-12 = 6.022 x 1023C-12 atoms
Common BULK Units Number of items Bulk Quantity • 1 dozen donuts • 1 GrosSof beads • 1 Score of years • 12 donuts • 144 beads • 20 years Chemisty BULK Unit is the Mole Bulk Quantity Number of items/particles • 6.022 x 1023Na atoms • 6.022 x 1023H2O molecules • 1 molENa atoms • 1 Mol H2O
Chemisty BULK Unit is the Mole mol The unit mole is abbreviated as _________. In equations, a mole is represented the symbol ____. n 1 mol of anything = 6.022x 1023of that thing The number 6.022 x 1023is called ___________________________. Avogadro’s Number In equations, a Avogadro’s Number is represented the symbol ____. NA
A Moleof Various Elements 6.022 x 1023 atoms 6.022 x 1023 atoms 6.022 x 1023 atoms 6.022 x 1023 atoms 6.022 x 1023 atoms
Molar Mass Average Atomic mass ________________ represents the mass of ______atom in atomic mass units (u) ONE 22.99 1 Na atom = _________ u. grams ____________________ is the mass in __________ of a ___________ quantity. Molar mass 1 Mole _____________ Na atoms = _______grams. 6.022 x1023 22.99
Average atomic mass (9.01218 u/1 atom) Molar Mass (9.01218 g/ mol of atoms) Be Molar Mass = MASS in grams of 1 mole
The Periodic Table Provides Molar Mass Molar Mass = MASS in grams of 1 mole 1 mol “Stuff”= 6.022 x 1023 pieces of “Stuff”
The Periodic Table Provides Molar Mass Molar Mass = MASS in grams of 1 mole 1 mole carbon = 12.01 g 6.022 x 1023 C atoms = 12.01 g 1 mol “Stuff”= 6.022 x 1023 pieces of “Stuff”
The Periodic Table Provides Molar Mass Molar Mass = MASS in grams of 1 mole 1 mole carbon = 12.01 g 6.022 x 1023 C atoms = 12.01 g 1 mol “Stuff”= 6.022 x 1023 pieces of “Stuff”
The Periodic Table Provides Molar Mass Molar Mass = MASS in grams of 1 mole 1 mole sulfur = 32.06 g 6.022 x 1023 S atoms = 32.06 g
Calculating Molar Mass The molar mass of a substance is represented by the symbol MM (or M). The unit of molar mass is g/mol. To find the molar mass of an element, simply read off the atomic mass on the periodic table and use the unit g/mol. E.g. What is the molar mass of iron? MMFe = 55.845 g/mol
Calculating Molar Mass of a compound To do this find the total of the masses of all the elements in the compound. E.g. What is the molar mass of sodium carbonate (Na2CO3)? MM = 2(MMNa) + MMC + 3(MMO) = 2(22.99)+12.011+3(15.999) g/mol = 105.99 g/mol