Ch 10: The Mole. Mole : a counting unit in chemistry 6.02 x 10 23 (atoms, molecules, formula units, paper clips, donuts, people, anything!) 602,000,000,000,000,000,000,000. Analogies: A pair means 2 A dozen means 12 A gross means 144 A score means 20
6.02 x 1023
(atoms, molecules, formula units, paper clips, donuts, people, anything!)
A pair means 2
A dozen means 12
A gross means 144
A score means 20
***a mole is just a word to represent a really large number
Why do we use a mole??
We need a very large number of atoms or molecules to measure because atoms and molecules are so small.
A mole of hockey pucks would be equal to the mass of the Moon.
2. If we have 4.3x1022 molecules of H2O, how many moles of H2O do we have?
4.3x1022 molecules of H2O x 1 mole ofH2O
= .071 moles of H2O
Formula Mass: mass of 1 molecule (covalent) or formula unit (ionic) of a substance. (unit = amu)
4. What is the mass of 1 mole of CH4?
Go to the lab and measure out 1 mole of a substance and put it in a ziplock bag.
Label with your name, substance and the mass in grams.
2. 100.0 g of NaNO3 = _________ mol of NaNO3