GC intro to mole notes filled in.notebook
November 28, 2012
The Mole
What is a mole in chemistry?
Nov 30­7:31 AM
What is a mole...?
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•
•
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A mole is simply an amount.
Like 1 dozen = 12 "things"...
1 mole = 6.02 x 1023 atoms or molecules
1 mole also = molar mass in grams
1 mole = 6.02 x 1023 atoms or molecules = molar mass (grams)
6.02 x 1023 is called Avogadro's Number
Nov 30­7:33 AM
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GC intro to mole notes filled in.notebook
November 28, 2012
1 mole = a HUGE number
Why??:
6.02 x 1023 = 602,000,000,000,000,000,000,000
Scientific Notation...
• positive exponent = move decimal place to the
right that # of times (# > 1)
Example: 1.25 x 1012 is the same as....
• negative exponent = move decimal place to the
left that # of times (# < 1)
Example: 1.25 x 10-5 is the same as...
Nov 30­7:33 AM
"Mole Facts"
1. 1 mole of donut holes would cover the surface of
the earth in a layer 5 miles deep.
2. 1 mole of blood cells would be MORE than the
total number of blood cells found in every human on
earth.
3. If you had 1 mole of pennies and gave away $1
million in pennies to EVERY person on earth EVERY
day…it would take more than 3000 years to give all
the coins away.
4. 1 mole of marshmallows would cover the ENTIRE
United States in a layer 600 miles deep.
Nov 30­7:33 AM
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GC intro to mole notes filled in.notebook
November 28, 2012
Entering Scientific Notation into your calculator...
To enter 6.02 x 1023....
• use the "Exp" or "EE" key
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"Exp" or "EE" takes the place of "...x 10..."
type in 6.02
hit the "Exp" or "EE" key
type in the exponent "23"
Dec 3­7:50 AM
Example Problem 1:
How many moles are contained in 150 grams of NaCl?
Step 1: Write down the given with units.
150 grams
Step 2: Draw a line and a "1" under the given.
150 grams
1
Step 3: Write "x" sign and a line (conversion factor).
150 grams x ________
1
Step 4: Write the same units as the given on the
bottom of the conversion factor.
150 grams x ______________
1
grams
Step 5: Write the units for what the problem is
asking you to find on the top of the conversion factor.
150 grams x _________moles_
1
grams
Step 6: Fill in the numbers in the conversion factor by
matching the units to the corresponding number in the
mole relationship...
1 mole = 6.02 x 1023 atoms or molecules = molar mass (g)
150 grams x ___1 mole
1
58.5 grams
Step 7: Do the math. Round answer to 1 decimal
place. Include units on your answer.
150 grams x ___1 mole
= _150_ = 2.6 moles
1
58.5 grams
58.5
Nov 30­7:43 AM
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GC intro to mole notes filled in.notebook
November 28, 2012
1 mole = 6.02 x 1023 atoms or molecules = molar mass (g)
Example Problem 2: pg. 8 #8
How many molecules are in 0.0130 moles of sulfur
trioxide?
Nov 30­7:53 AM
1 mole = 6.02 x 1023 atoms or molecules = molar mass (g)
Example Problem 3: pg. 9 # 14
What is the mass in grams of 2.96 x 1026 atoms of
zinc?
Dec 3­7:30 AM
4
GC intro to mole notes filled in.notebook
November 28, 2012
Now you try...
1 mole = 6.02 x 1023 atoms or molecules = molar mass (g)
Example Problem 4: pg. 8 # 4
How many grams is 4.23 moles of oxygen?
Dec 3­7:32 AM
HOMEWORK...
Finish pgs. 8 & 9 in the
mole packet
Dec 3­7:39 AM
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