1) The document discusses the relationships between the number of particles, molecules, ions, and atoms that make up different chemical substances using moles as the unit of measurement. 2) Key relationships shown include that the number of particles in 1 mole of a substance is equal to Avogadro's constant, and the number of molecules, ions or atoms can be calculated by multiplying the number of moles by Avogadro's constant and taking into account the chemical formula. 3) Examples are provided to demonstrate calculating the number of molecules, ions and atoms given the number of moles of different substances like carbon, hydrogen gas, water and sodium chloride.

1. MATTER AROUND US
CHEMICAL FORMULAE AND
EQUATIONS
X NA
1 Mole
9
5 4.816 x 1023 Particle
3.01
6.02 24
÷ NA

2. C
C
ATOM
Number of mole
atom
Particles
MOLECULE Number of mole
molecule
ION Number of mole
ion

3. Example
C Count number of atom in 0.4 mole atom carbon.
Solution:
0.4 mole ? Atom carbon
Number of mole Get the
atom carbon = 0.4 information
mole from question
So, number of atom carbon is,
use the
= 0.4 x Avogadro constant relationship
= 0.4 x 6.02 x 1023 atom in figure 1
= 2.48 x 1023 atoms

4. Relationship for
x NA x depending on formulas chemistry
Number of mole
Number of molecule Number of atom
molecule
÷ NA ÷ depending on formulas chemistry
O
H
2 mole molecule H2 Molecule H2 = Atom H =
2 x NA 2 x NA x 2

5. Example
There are 3 mole gases hydrogen, H2 in one container, Count;
• Number of molecule hydrogen, H2
• Number of atom hydrogen
Solution :
Number of mole molecule hydrogen, H2 = 3 mole molecule hydrogen, H2
Get the information
from the question
3 mole molecule of hydrogen, H2 ? Molecule hydrogen, H2
a) So, number of molecule hydrogen, H2 ;
Use the
= 3 x Avogadro Constant relationship in
= 3 x 6.02 x 1023 molecule figure 2
= ___________ molecule

6. There are 3 mole gases in one container,
b) Number of atom hydrogen
3 x 6.02 x 1023 molecule hydrogen, H2 ? Atom hydrogen
Analysis
b) Every molecule hydrogen, H2 consist of 2 atom
formulae
hydrogen. So, number of atom hydrogen in the gas container; molecule H2
= 2 x number of molecule hydrogen, H Use the
= 2 x 3 x 6.02 x 1023 atom relationship in
= ______________ atom figure 2
H H

7. EXAMPLE
Molecule of water H2O
Sample of water consist of 1.806 x 1024
molecules, count;
O
• Number of mole water H H
molecule
• Number of atom oxygen
• Number of atom hydrogen
in the sample.

8. Solution;
1.806 x 1024 molecule ? Molecule
water water
a) Number of molecule water = 1.806 x 1024
Get the
So, number of mole molecule water; information from
= 1.806 x 1024 ÷ NA question
= 1.806 x 1024
6.02 x 1023
= 3 mole molecule of water

9. 1.806 x 1024 molecule ? Molecule
water water
b) 1 molecule water consist 1 atom oxygen
So, 1.806 x 1024 molecule of water consist of
1.806 x1024 atom of oxygen
O
H H

10. c) Every molecule water, H2O consist of 2 atom
hydrogen. So, number of atom hydrogen in the
sample;
= 2 x number of molecule hydrogen. H
= 2 x 2 x 6.02 x 1023 atom
= 4 x 6.02 x 1023 atom
= 2.408 x 1024 atom
O
H H

11. Relationship for
x depending on formulas
x NA chemistry
Number of
mole ion Number of unit Number of ion
÷ NA ÷ depending on formulas
chemistry

12. Example
Count number of units in 4 mole NaCl.
Solution;
1 mole substance 6.02 x 1023 units
So;
4 mole NaCl = ? units
4 mole NaCl = 4 x 6.02x 1023
= 2.408 x 1024 units NaCl

13. Count number of ions of Cl- in 4 mole NaCl.
One units of NaCl have 1 ion Cl-
So;
One mole unit of NaCl ? ion Cl-
1 mole units of NaCl = 6.02 x 1023 ions
4 mole units of NaCl = 4 x 6.02 x 1023 ions
= 2.408 x 1024 ions