## Monday, January 24, 2011

### M-1/24-Stoichiometry

1.  We picked up four sheets in class today (Mol Notes- 1page, and Pair,Dozen, Mol Lab Activity- 3pages)

Mr. Tucker mentioned that second semester involves a bit more problem solving and that if we do not stick with the 10-15min a night we might fall behind.....MAKE SURE TO PERFORM NIGHTLY ASSIGNMENTS!!!!

2.  We then talked about the mole concept and filled out one page of notes:
*  A pair is 2 of something
A dozen is 12 of something
A mole is 6.02 x 1023 of something (this is useful for counting particles/atoms/molecules)

*A mole is then equal to this number above as well as ____g/mol as found on the periodic table
(for instance, 1 mole of Carbon is 12.01g/1mole and 1 mole of Aluminum is 26.98g/1mole)

*  the ratios are then 1mol/6.02 x 1023 or 1mol/___g   (we can use these as conversion factors)

*  We then filled out a mole island conversion chart.  This helps to know when to use the conversion factors in mole problems.

3.  We then performed the Pair, a Dozen, A Mole Activity
*again, a pair is 3 of something, a dozen is 12 of something, and a mole is 6.02 x 1023 of something
* we did a few calculations together:
2.5moles of donuts  x   6.02 x 1023 donuts     =   1.505 x 1024 donuts
1 mole donuts

*  Next, we looked at a big chunk of Aluminum foil.  It was 26.98g of it.  This means that we also had 1 mole of it (because this is the molar mass found on the periodic table for Aluminum) and also that we had 6.02 x 1023atoms of Aluminum (since 1 mole of something is always 6.02 x 1023 of that thing)

*Finally, we poured 18ml of water in a graduated cylinder (since water has a density of 1g/ml this means that we also had 18g of water in the graduated cylinder).   When we looked at the periodic table (H=1g/mole and O=16g/mol, and water has a formula of H2O) we figured out that 1 mole of water will have a mass of 18g/mol.  This means that in the graduated cylinder we also had 1mol of water!!!!  It really wasn't that exciting, but Mr. Tucker seemed to think so, so hence the exclamation points.  Then, since we had 1mole fo water in the graduated cylinder we must also have 6.02 x 1023  water molecules in the cylinder as well!!!

HOMEWORK:
*  Meet in the science lab tomorrow
*   Transfer the mol island chart from our notes to the small notecard....we should use this when performing mole problems till we get the hang of it