Post on 26-Mar-2015
Catalyst – 22+33-1, 2.009 * 103
Welcome Back!Monday Mystery
Element!1. Like many rare earth
elements, is used to make phosphors in TVs
2. Attracted to magnets3. Oxides of this element
flake off during tarnishing
Weekly Goal!
Catalyst – 22+33-1, 2.009 * 103
Welcome Back!Monday Mystery
Element!1. Like many rare earth
elements, is used to make phosphors in TVs
2. Attracted to magnets3. Oxides of this element
flake off during tarnishing
Gadolinium
Today’s Agenda
Catalyst Debrief: What needs to happen
the rest of the semester to ensure success!
Unit 5 Test Tracking and Review Holy Moley! Work Time Exit Question
Today’s Objectives
SWBAT get ready to DOMINATE the rest of the semester – 3 more weeks!
SWBAT describe the mole. SWBAT perform stoichiometry
to convert between moles and molar mass.
Our Class Mastery – 2nd Period
HOW DID WE DO????
65%
Our Class Mastery – 2nd Period
HOW DID WE DO????
60%
Our Big Goal!!!
Do you remember what it is???
That’s right! 80% mastery or higher of GLEs!
We can still do it…But it will take a lot of hard
work!!!
Ways to improve our class mastery
How do YOU think we can get it done???Improve class ATTENDANCE!
FOCUS during class!ASK questions and/or come in for
TUTORINGComplete ALL class and homework
Study EFFECTIVELYHave someone quiz you, cover up notes
and see what you remember, pinpoint areas for improvement, etc.
Chemistry CANES need to be/need to…
CConsiderate
AAmbitious
NNever give up
EExcellent
SStrong
New Personal Motto (5 minutes)Take one post-it note and write your personal motto for the rest of the semester.
Write down the words you will live by for the next 3 weeks.
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?????!!!???!?!?!???!!!!
The Mole
Think of the term “a dozen”…
How many donuts are in a
dozen?
How many eggs are in a
dozen?
The Mole
Just like a dozen refers to 12 objects…
The Mole
Just like a dozen refers to 12 objects…
… the mole refers to …
The Mole
Just like a dozen refers to 12 objects…
… the mole refers to …
6.02 x 1023
particles
The Mole
This number is called Avogadro’s number…
6.02 x 1023
602,000,000,000,000,000,000,000
Avogadro’s Number
1 mol = 6.02 x 1023 atoms
1 mol = 6.02 x 1023
molecules
Why do YOU know this?
The Mole
Key Point #1: The mole is a unit of measurement used in chemistry.
Interpreting Equations
4 Fe + 3 O2 2 Fe2O3
“4 moles of iron react with 3
moles of oxygen gas toproduce 2 moles of iron(III)
oxide”Coefficients in chemical
reactions just refer to how many moles are reacting!
Interpreting Equations
C3H8 + 5 O2 3 CO2 + 4H2O
“1 mole of propane (C3H8)reacts with 5 moles of oxygen
gas to produce 3 moles of carbon
dioxide and 4 moles of water”
How many moles needed?(moles – moles)
C3H8 + 5 O2 3 CO2 + 4H2O
If you start with 10.0 molesof propane (C3H8), how many
moles of oxygen gas is neededto fully combust (react)?
How many moles produced? (moles – moles)
C3H8 + 5 O2 3 CO2 + 4H2O
If you start with 10.0 molesof propane (C3H8), how manymoles of carbon dioxide will
be produced?
What’s the point of all this?
Key Point #2: Stoichiometry relates the amount of REACTANTS with the amount of PRODUCTS. It all relates back to the mole…
Scientists use stoichiometry to plan reactions! And guess what else is coming back….
Working on the Railroad
Step 1: What to what?
Step 2: Write conversion factor(s)
Step 3: Train tracks
Avogadro’s Number
1 mol = 6.02 x 1023 atoms
How many atoms are in .25 mol N2?
Avogadro’s Number
1 mol = 6.02 x 1023 atoms
How many atoms are in .25 mol N2?.25 mol N2
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…
Your turn! Whiteboards.
How many atoms are in 1.1 moles of C12H22O11?
OOOH, I want some more train tracks!
Key Point #3: Molar mass is the amount of grams in one mole of a substance.
But Ms. Stroh, how am I ever going to find out this information?
Molar Mass
1 mol C =
Molar Mass
1 mol C = 12 g C
Molar Mass
The atomic weight of an atom is also the molar mass of that atom.
Carbon has an atomic weight of 12.01.
In 1 mole of carbon, there are 12.01 grams.
In 1 mole of sodium, how many grams are there?
Molar Mass
1 mol Na =
Molar Mass
1 mol Na = 23 g Na
Molar Mass-Can you figure out this one??
1 mol CO2 =
Molar Mass
1 mol CO2 =
C = 12 g O = 16 gO = 16 g
Molar Mass
1 mol CO2 =
C = 12 g + O = 16 g + O = 16 g
Molar Mass
1 mol CO2 = 44 g CO2
C = 12 g + O = 16 g + O = 16 g
Molar Mass
1 mol KNO3 =
K = + N = + O =
Molar Mass
1 mol KNO3 =
K = 39 g + N = 14 g + (3) O = 16 g
Molar Mass
1 mol KNO3 = 101 g
K = 39 g + N = 14 g + (3) O = 16 g
Exit Question
1. What is a mole?2. Calculate the
molar mass of H2CO3.
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?
Molar Mass
1 mol CH4 =If we have 20 grams CH4, how many
moles of CH4 do we have?
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.
Exit Question
1. How many molecules are in a mole of NH4?
2. How many grams are there in 2.3 moles of NH4?