SIM for Atoms:Grade 8 Science

1. ATOMS : ARE
YOU IN?
Mrs. Esmeralda D. Gamil
Teacher 1
Imelda National High School
Imelda, Zamboanga Sibugay
SELF-INSTRUCTIONAL MATERIAL

2. METADATA
COMPETENCY TITLE
OF THE
SIM
TYPE
(Card,
Video,Presenta
tion, Booklet,
Chart, etc.)
Grade
Level
Subject
Area
Brief Description Type Of
Learners
Determine
the number of
protons,
neutrons, and
electrons in a
particular
atom.
Atoms:
Are
you in?
Booklet Grade 8 Science This self-Instructional Material
aims to enhance knowledge of
students about atoms. This will
help the students to understand
what really atoms is.
After the end of this topic the
students will be able to
illustrate atoms, differentiate
components of the atoms, how
do these components arrange.
And relate the importance of
atoms to our daily life.
Average,
slow

3. What happened?
PRETEST
1. What do you called of the positive charge of an atom
a. neutron b. proton c. electron d. none of these
2. Who proposed the plum pudding model?
a. J.J. Thomson b. Ernest Rutherford c. Ernest Marsden c. Wilhelm Geiger
3. Atoms are stable if it has :
a. Equal number of protons and neutrons
b. Equal number of neutrons and electrons
c. Equal number of protons and electrons
d. Unequal number of protons and electrons
4. How will you identified an isotopes?
a. through its atomic number
b. through its electronegativity
c. through its ionization energy
d. through its mass number
5. When an atom gain or lost electrons, what will happen to an atom?
a. Become an ion b. Become an electron c. Become a proton d. Become a neutron
6. If an atom has 5 protons, how many electrons does this atom have?
a. 4 b. 5 c. 6 d. 7

4. What happened?
7. Isotope Nitrogen-14 has 7 protons, how many are the electron and
neutrons?
a. 6 electrons and 6 neutrons c. 7 electrons and 7neutrons
b. 7 electrons and 6 neutrons d. 5 electrons and 7 neutrons
8. Using the periodic table what element with an atomic number of 15?
a. Carbon b. lithium c. sodium d. phosphorus
9. Among all the elements, which element has the smallest number of protons
in its atom?
a. Hydrogenb. Helium c. Carbon d. Lithium
10. The isotope Boron has 5 # of proton, does it has also 5 # of electrons ? (If
the answer is no, give the correct answer)
a. Yes b. No c. Yes

5. What happened?
11. The isotope Magnesium -24 has 24 # of electrons? How many are the protons?
a. 20 b. 23 c. 25 d. 24
12. Among the elements sodium, Silver, Selenium, Potassium, hydrogen which of
these has the highest atomic mass?
a. Sodium b. Selenium c. Silver d. Hydrogen
13. Which statement below is correct?
a. Fluorine has 10 neutrons and 9 protons
b. Fluorine has 9 neutrons and 10 protons
c. Fluorine has 9 neutrons and 9 protons
d. Fluorine has 10 neutrons and 10 protons
14-15 .Write the correct shorthand notation of the element hydrogen and helium
respectively.

6. TABLE OF SPECIFICATION
TOPIC No. of
Days
Taught
No. of
Items
Remembering Understanding Applying Analyzing Evaluating Creating
Atoms: Are
you in?
10 HRS. 15 1,2 3,4,5, 6,7,8 9,10,11 12,13 14,15

7. .
What do you need to know?
Atoms, of which all objects are
made, are electrical in nature. Atoms
contain particles with positive and
negative charges. The proton carries a
positive charge (+1). The electron carries
a negative charge (-1). Atoms, in their
most stable state are neutral with an
equal number of protons and electrons.
Objects are
electrically
neutral, or simply,
neutral, but they
carry electrical
charges.

8. Subatomic
particle
(symbol)
Charge
Mass,
grams
Location in the
Atom
Electrons (e-) -1
9.109 x 10-
28 Outside nucleus
Protons (p+) +1
1.672 x 10-
24 Nucleus
Neutrons (n0) 0
1.675 x 10-
24
Nucleus
Some properties of the three main subatomic particles
Electrons are very much
lighter than the protons
and neutrons, to the
point that its mass does
not significantly
contribute to the mass of
the entire atom. In effect,
the mass of the electron
is negligible.the protons and
neutrons are called
nucleons.
The nucleons,
tightly packed
together, form the
nucleus in the
center of the atom.
What do you need to
know?

9. Towards the 19th century, J.J.
Thomson was able to discover that
atoms have negatively-charged
particles, which he called electrons.
It led him to propose a new model
for the atom, which he called the
plum pudding model.
A group of scientists
composed of Ernest
Rutherford, Johannes
"Hans" Wilhelm Geiger
and Ernest Marsden
tested Thomson’s model
by bombarding a very
thin sheet of gold foil
with positively-charged
alpha particles. Their
experiment is referred to
as the alpha particle
scattering experiment.The nuclear model by
Rutherford. This model
replaced the one
proposed by Thomson
and is the model that
we hold to this time,
with respect to the
placement of the
nucleus in the atom.
What do you need to know?

10. Do you know that……..
What we do know, however, are the
following: (1) The electron although it
is negatively charged does not
collapse into the positively charged
nucleus; (2) There is attraction
between the nucleus and the electron,
evidence of which is that energy is
required to remove an electron from
the atom.
All atoms of an
element contain the
same number of
protons in their
nuclei. This number is
the element’s atomic
number
Atoms having the same
number of protons but
different number of
neutrons are referred as
isotopes.
The isotopes are identified
through their mass number
which is the sum of the number
of protons and the number of
neutrons in an atom.
A shorthand
notation for
isotope includes
the element’s
symbol and mass
number, for
instance, Ca-40.

11. What have you learned?
Activity 1. Fill out the missing data on the table below
Subatomic particle (symbol) Charge Mass, grams Location in the Atom
Electrons (e-) 9.109 x 10-28 Outside nucleus
Protons (p+) +1 Nucleus
Neutrons (n0) 1.675 x 10-24
Activity1

12. Activity 2
Isotope Element Name # of p+ # of e- # of n0 Charge
B-6 Boron 5 1 0
N-14 Nitrogen 7 0
Fluorine 9 10 -1
Neon 10 10
Mg-24 12 10
Al-27 +3
Si-28 14
S-32 0
K-35 +1
Complete the
table below.

13. Post test
1. What do you called of the positive charge of an atom
a. neutron b. proton c. electron d. none of these
2. Who proposed the plum pudding model?
a. J.J. Thomson b. Ernest Rutherford c. Ernest Marsden c. Wilhelm Geiger
3. Atoms are stable if it has :
a. Equal number of protons and neutrons
b. Equal number of neutrons and electrons
c. Equal number of protons and electrons
d. Unequal number of protons and electrons
4. How will you identified an isotopes?
a. through its atomic number
b. through its electronegativity
c. through its ionization energy
d. through its mass number
5. When an atom gain or lost electrons, what will happen to an atom?
a. Become an ion b. Become an electron c. Become a proton d. Become a neutron
6. If an atom has 5 protons, how many electrons does this atom have?
a. 4 b. 5 c. 6 d. 7

14. 7. Isotope Nitrogen-14 has 7 protons, how many are the electron and
neutrons?
a. 6 electrons and 6 neutrons c. 7 electrons and 7neutrons
b. 7 electrons and 6 neutrons d. 5 electrons and 7 neutrons
8. Using the periodic table what element with an atomic number of 15?
a. Carbon b. lithium c. sodium d. phosphorus
9. Among all the elements, which element has the smallest number of protons
in its atom?
a. Hydrogenb. Helium c. Carbon d. Lithium
10. The isotope Boron has 5 # of proton, does it has also 5 # of electrons ? (If
the answer is no, give the correct answer)
a. Yes b. No c. Yes
Post test

15. 11. The isotope Magnesium -24 has 24 # of electrons? How many are the
protons?
a. 20 b. 23 c. 25 d. 24
12. Among the elements sodium, Silver, Selenium, Potassium, hydrogen which
of these has the highest atomic mass?
a. Sodium b. Selenium c. Silver d. Hydrogen
13. Which statement below is correct?
a. Fluorine has 10 neutrons and 9 protons
b. Fluorine has 9 neutrons and 10 protons
c. Fluorine has 9 neutrons and 9 protons
d. Fluorine has 10 neutrons and 10 protons
14-15 .Write the correct shorthand notation of the element hydrogen and
helium respectively.
Post test

16. Answer Card
1.A
2. A
3.C
4. D
5.A
6.b.
7.c.
8.D
9. A
10.C
11.D
12.C
13.c
14. 1 H +!
15. 2 He-1
Subatomic
particle
(symbol)
Charge Mass, grams
Location in the
Atom
Electrons (e-) -1 9.109 x 10-28 Outside nucleus
Protons (p+) +1 1.672 x 10-24 Nucleus
Neutrons (n0) 0 1.675 x 10-24 Nucleus
Isotope Element Name # of p+ # of e- # of n0 Charge
B-6 Boron 5 1 0
N-14 Nitrogen 7 7 7 0
F-19 Fluorine 9 10 10 -1
Ne-20 Neon 10 10 10 0
Mg-24 Magnesium 12 10 12 +2
Al-27 Aluminum 13 10 14 +3
Si-28 Silicon 14 14 14
S-32 Sulfur 16 16 16 0
K-35 Potassium 19 18 16 +1
Pretest/Posttest Activity
1
Activity 2

17. Reference
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2. CANBERRA CITY, A.C.T., AUSTRALIA.
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• ELVINS, C., JONES, D., LUKINS, N., MISKIN, J., ROSS, B., & SANDERS, R. (1990). CHEMISTRY
ONE: MATERIALS, CHEMISTRY IN EVERYDAY LIFE. PORT MELBOURNE, AUSTRALIA:
HEINEMANN EDUCATIONAL AUSTRALIA.
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• HILL, J.W. & KOLB, D.K. (1998). CHEMISTRY FOR CHANGING TIMES (8TH ED.).UPPER
SADDLE RIVER, NJ: PRENTICE HALL.
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• PHILIPPINES. DEPARTMENT OF EDUCATION. (2004). CHEMISTRY: SCIENCE AND
TECHNOLOGY TEXTBOOK FOR 3RD YEAR. (REVISED ED.). QUEZON CITY: AUTHOR.
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• SILBERBERG, M.S. (2007). PRINCIPLES OF GENERAL CHEMISTRY. MCGRAW-HILL: NEW
YORK
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• LINK
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• INTERACTIVE SIMULATIONS. (N.D.). RETRIEVED FROM HTTP://PHET.COLORADO.EDU/