moley, moley, mole… objective: swbat perform stoichiometric conversions from mole to mass, from...
TRANSCRIPT
Moley, moley, mole…
Objective: SWBAT perform stoichiometric conversions
from mole to mass, from mass to mass
Catalyst: What is .25 of a dozen? If a dozen hotdogs weighs 3 kilograms, how much does 3 dozen hotdogs weigh?
What is a mole to us chemists? A benign overgrowth of cells because of
a failure in mitosis? NO! But gross… A rascly little rodent? NOOOO! A TV show featuring celebrities? NOOOOO! Then WHAT IS IT?????!!!???!?!?!???!!!!
ATTENTION! ATTENTION!
Today’s goal is for you to learn how to “Set-up” these problems. Therefore, even if you do not have a calculator you need to make sure that you set-up the problems in your notes.
What’s the point of all this?
Key Point #1:Avogadro's number is used to convert between grams, moles, and atoms/molecules.
It all relates back to the mole…
Guess what’s coming back…
Avogadro’s Number
Conversion factor:
1 mol = 6.02 x 1023 atoms
1 mol = 6.02 x 1023 molecules
1 mol of pennies = ?
You may want to copy this down…hint hint cough cough
Avogadro’s Number
1 mol = 6.02 x 1023 atoms
How many atoms are in .25 mol N2?
.25 mol N2
1 mol N2
6.02 x 1023 atoms
I guess you can use your calculator for this…
Scientific Notation on the calculator If you need to type 6.02 * 1023
Type “6.02 ‘EE’ 23” instead.
SAVE TIME AND LOOK COOL!
OOOH, I want some more train tracks! Key Point #2:
Molar mass is the total mass in one mole of a substance.
1 mol X = ____ g X
BUT HOW DO WE FIND THE MASS???
1 mol Oxygen = 16 g 1 mol of He = ?
Molar Mass- Let’s try a problem
1 mol KNO3 = 101 g If we have 3.5 moles of KNO3, how many
grams would we have?
WHAT to WHAT?
Independent Practice
1, 11, 16… we will go over to show you how to solve this hilarious assignment!
Attach your work on a separate sheet of paper.