Transcript The mole:

The mole in a hole review:
Basic problems:
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We worked one step mole problems going from moles to
grams or grams to moles
We worked one step mole problems going from moles to
atoms or molecules and from atoms or molecules to moles.
HOLY MOLEY is that mind bongling!!
The key is to always start with the given (the actual number
and unit) and set up a template to convert to the find.
What you don’t want goes on the bottom to be cancelled,
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the number 1 goes in front of mole
the number 6.02 x 1023 goes in front of molecule or atom
the mass numbers added from the periodic chart go with grams.
Let’s work a problem together
in your notebook…today is 2/1
Yes… even if I am not here today you need to do this!
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Circle the given, underline find
Set up a template for one or two steps
Label the final units!!
There are 1-step and 2-step problems. If a problem
does not have the word ‘mole’ in it… you must add it
in the conversion steps because it is a 2-step..
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23
How many
 2.5g (1 mo.) (6.02x10 molecules
molecules of
(122.5g) ( 1 mo.)
potassium chlorate
are in a 2.5g
= 2.5 x 6.02 x 1023
sample, like in the
lab we just did?
122.5
(each click will reveal a st
ep… so don’t click until
you have the template set-up
and formula mass calculated.)
(calculate before you click the answer)
= .123 x 1023 or 1.23 x 1022
molecules of
KClO3
Once you get
better at
converting you
can jump
between the
triangles in this
diagram.
Problems:
1. How many molecules are in 6.02 moles of NaCl?
2. How many molecules are in 6.02 moles of
barium chloride?
3. How many molecules are in 6.02 grams of
sodium chloride?
4. How much does 6.02 molecules of mercury(I)
chloride mass out to?
5. Based on problem #4, what is the percent of
chlorine in the compound?
6. How many grams would this be in a 53.5g sample?
7. What is the % of oxygen in potassium chlorate?
You are going to check the 6 problems worked on.
1. How many molecules are in 6.02
moles of sodium chloride?
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A. Do you need to know the  Not really
correct formula for the
sodium chloride?
 Not at this point
B. Do you need to know the
mass of sodium chloride?
 6.02 moles
C. What do you have?
 Molecules
D. What do you want?
 6. 02(6.02) 1023=
E. What is the answer?
36.04 x 1023 molecules
2. How many molecules are in
6.02 moles of barium chloride?
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 6.02 moles
A. What do you have?
 Molecules of BaCl2
B. What do you want?
C. What goes on the bottom? Moles
D. What is the answer?
23 molecules
 6.02 (6.02) x 10
of BaCl2 = 36.24 x 1023
Bonus:
How many atoms is this?
3 total atoms are in 1 molecule,
so 3(36.24) x 1023 =
108.7 = 109
3. How many molecules are in
6.02 grams of sodium chloride?
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6.02 g NaCl x 6.02 x 1023 molecules
58.5 g NaCl
=
.619494 = .619 x 1023 molecules or 6.19x 1022 molecules
4. How much does 6.02 molecules of
mercury(I) chloride mass out to?
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A. What is the
 Hg2Cl2
correct formula for
mercury(I)
chloride?
 2(35.5) + 2(200.5) = 472g
How much does 1
mole of it mass?
What is the answer 6.02molecules( 1mole ) (472g)
to #4?
(6.02x1023molecule) (1mo)
= 472 x 10-23 g
Based on problem #4, what is the percent of
chlorine in the compound (the % Cl in an
entire mole of mercury(I) chloride?
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There are two atoms of chlorine for
every 2 atoms of mercury.
That means 71.0g Cl in 472g total
71/472g x 100% = 15.0%
6. How many grams would this be in a
53.5g sample?
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15% of 53.5 =
(.15)53.5= 8.025 = 8.03g of Cl
7.What is the % of oxygen in potassium
chlorate (from lab)?
K= 39.0
Cl=35.5g
O=16.0 x 3 = 48g
KClO3 = 122.5
Oxygen = 48/122.5 x 100% = 39.2%