This document discusses the mole concept in chemistry. A mole is the amount of a substance that contains 6.022x1023 elementary entities and can be used to quantify atoms, molecules, ions or other particles. The mass of a mole of a substance is equal to its molar mass in grams. Some examples given are that 1 mole of oxygen is 16 grams, 1 mole of carbon is 12 grams, and 1 mole of iron is 56 grams. The document also notes that Avogadro's number, which is 6.022x1023, is defined as the number of elementary entities in 1 mole of a substance.

1. REVIEW
Compute the percentage
1. water (H2O)
2. Vinegar (C2H3O2)

2. THE
MOLE CONCEPT
SCIENCE 9

3. LETS PLAY
KAHOOT

4. THINK ABOUT THIS!
HAVE YOU EVER WONDERED HOW
MANY STARS ARE THERE IN THE SKY?
CAN YOU COUNT ALL THE STARS?
How about such as tablespoon of sugar
or a tablespoon of salt?

5. THINK ABOUT THIS!
you are aware, atoms and molecules are so small that we
cannot see them with our naked eyes or even with the help of
a microscope. Any sample of matter which can be studied
consists of extremely large number of atoms or molecules.
Therefore, it would be pertinent if we could specify the total
number of atoms or molecules in a given sample of a
substance. We use many number units in our daily life. For
example, we express the number of eggs in terms of ‘dozen’. In
chemistry we use a number unit called mole.

6. THINK ABOUT THIS!
A mole is the amount of a substance that contains as many
elementary entities, thus mole is a number unit for dealing with
elementary entities such as molecules.
The term mole has been derived from the Latin word ‘moles’
which means a ‘heap’ or a ‘pile’. It was first used by the famous
chemist Wilhelm Ostwald more than a hundred years ago.

7. THINK ABOUT THIS!
1 mole of any element is equivalent to dependent
atomic mass
1 mole of Oxygen = 16
1 mole of Carbon = 12
Molar mass is equivalent to total atomic mass
O2 = 2 x 16 = 32g CO = 12 + 16 = 28g
Fe = 1 x 56 = 56g

8. THINK ABOUT THIS!
1 mole of any Element, molecules or compound is
equivalent to 6.02 ×1023 number of atoms

9. He was an Italian scientist.
He is most noted for his contributions to
molecular theory, including what is known
as Avogadro's law.
In tribute to him, the number of
elementary entities,1 mole of a substance,
6.02214179×1023 is known as Avogadro’s
Number
AMADEO AVOGADRO

10. SAMPLE
How many moles are in 14 g of
cadmium?

11. SAMPLE
How many grams are in 4.63 x
1024 mole of CCl4?

12. SAMPLE
Calculate the number of atom in
8.33 grams of O2

13. SEATWORK
13 ADD A FOOTER MM.DD.20XX

14. SUMMARY
A mole is the amount of a substance that contains as
many elementary entities, thus mole is a number unit
for dealing with elementary entities such as molecules.
1 mole of any element is equivalent to dependent
atomic mass
Molar mass is equivalent to total atomic mass
1 mole of any Element, molecules or compound is
equivalent to 6.02 ×1023 number of atoms

15. THANK YOU!
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again see attachment in our
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GRADE 9 (SCIENCE)
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