Introduction to the Mole

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Introduction to the Mole
Please Return!
Directions: Do activity in your notebook, please do not write on this paper, but put all answer in your
notebook.
Read Ch 3.3 pg 82-84
Purpose: To discover a method of counting “things” that you are not able to see.
Intro:
1. When you buy eggs you usually ask for a _____ eggs. You know that one dozen of any item is _____.
2. Paper is not packaged by the dozen. Paper is packaged by a ream. A ream of paper has 500 sheets.
Why is it useful to use units like a dozen or a ream? _________________________________
3. What determines how many items should make up a particular unit? _____________________
4. If you were asked to design a new unit to count something, what would you consider when choosing
how many items should be included in your new counting unit?
5. Data:
How many items in each picture:
Item Number mice Candles books Question marks ANALYSIS AND INTERPRETATION
6. As you know, a dozen represents 12 items. Since I did not
have enough items to make a dozen, I decided to make a
new counting unit. I called this unit an OWL. Each of the
pictures contains _____ items. We will call this number of
items an OWL. If you understand the concept of OWL as a counting unit, just like a dozen for
counting by 12, you should be able to complete the following questions.
Questions
7. An OWL of oranges will have _____ oranges.
8. An OWL of pretzels has ____ pretzels. An OWL of desks has _____ desks.
9. An OWL of molecules of water has ____ molecules of water.
10. An OWL of particles has ___ particles.
11. An OWL of atoms of iron has _____ atoms of iron.
12. An OWL of formula units of salt has _______ formula units of salt.
Now that you understand the meaning of an OWL, you should be able to answer the following:
13. How many Hershey’s Kisses are in 2 OWLS? _______
14. How many caramels are in 10 OWLS? _______
15. How many Hershey’s Kisses are in 400 OWLS? _______
16. How many caramels are in 1/2 OWL? _____ 17. WRITE DIRECTIONS FOR FINDING THE # OF ITEMS IF GIVEN THE # OF OWLS. 18. How many pencils are in 20 OWLS? _______
19. How many oranges are in 5 OWLS? _______
20. How many pencils are in 0.5 OWLS? _______
21. How many pencils are in 0.25 (1/4) OWLS? _______
22. How many atoms of silver are in 20 OWLS? _______
23. How many molecules of water are in 10 OWLS? _______ Finding the Number of OWLS
If you are given the number of items you can tell the number of OWLS. For example, since one
OWL is 4 items, 8 items make up 2 OWLS.
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How many OWLS are 16 Hershey’s Kisses? ______
How many OWLS are 100 pretzels? ____
How many OWLS are 400 desks? ____
How many OWLS is 1 orange? ________ (Write a fraction or a decimal.)
How many OWLS are 2 caramels? _________
Write directions for finding the number of OWLS if given the number of pieces.
30. How many OWLS are 48 Hershey’s Kisses? ______
31. How many OWLS are 2 Hershey’s Kisses? ______
The Mole: As you can imagine, an OWL of molecules of water would be too small to see. Scientists had
toselect a bigger unit for counting molecules of substances. The unit scientists use is called a
MOLE. One MOLE of anything has 602,200,000,000,000,000,000,000 items. This number is called
AVOGADRO’S NUMBER and is usually written in scientific notation as 6.022 x 1023
One MOLE of anything has 6.022 x 1023 items.
Use the rules you have written for calculations involving OWLS to answer questions about MOLES. Remember to
use 6.022 x 1023 for the number of items in a MOLE. Recall how to multiply numbers written in scientific notation.
(see bottom on page)
[4 x 6.022 x 1023 : (6.022 x4)x1023 = 24.08 x 1023 = 2.408 x 1024].
Note: Atoms and molecules in these questions are words meaning items.
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How many Hershey’s Kisses make up 1 MOLE? _______
How many caramels make up 10 MOLES? _______
Find the number of atoms of sodium in 2 MOLES. _______
Find the number of molecules of water in 6 MOLES. _______
Find the number of caramels in 0.5 MOLES. ________
How many moles of caramels are 6.022x1023 of caramels? _______
How many moles of desks are 6.022x1023 of desks? ______
How many moles of pens are 12.04x1023 of pens? ______
How many moles of sodium atoms are 12.04x1023 of sodium atoms? _______
Reminder: One MOLE has 6.022 * 1023 items or there are 6.022 * 1023 items/mole.
Items may mean: caramels, Hershey’s Kisses, bananas, oranges, ATOMS, FORMULA UNITS, MOLECULES, IONS, etc.
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How many atoms of potassium make up one MOLE ? _____
How many atoms of potassium make up 2 MOLES? _____
How many formula units of salt make up 10 MOLES? _____
How many molecules of water make up 1 MOLE? _____
How many molecules of water make up 5 MOLES? _____
How many moles are 6.022 x 1023 atoms of sodium? _____
How many moles are 12.04 x 1023 atoms of carbon? _____
How many moles are 18.06 x 1023 atoms of sodium? _____
How many moles are 60.22 x 1023 atoms of sodium? _____
How many moles are 6.022 x 1023 molecules of water? _____
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