Physical Science Grade 11 or 12 ABM Strand K-12 Senior High School (Curriculum Guided)

1. Developmen
tof the AtomPrepared By: Jerome A. Bigael, Leyte Progressive High School

2. Thales of Miletus
(ca. 624-546 BCE) was
the first to ask and
propose an answer to
the question:
What is matter
composed off?
Ancient Gr reeksG
Thales thought of water (H2O) as the ultimate substance that
constituted matter because he believed that water could change
into any kind of matter.

3. Empedocles of Agrigentum
(492-432 BCE) considered air, water,
earth and fire as the four essential
elements that could possibly be the
source of everything- all kinds of matter.

4. Later on, Leucippus (5th century
BCE) and his student Democritus
(460-370 BCE) introduced the first
atomic theory by raising questions
on whether or not a substance could
be divided continuously.

5. Leucippus concluded that at
some point, one would arrive at
fragments that can no longer be
divided. Yet, those indivisible
fragments would still maintain
the characteristics of the original
material.

6. Leucippus is considered as
the first atomist but is less
well known compared to
Democritus who expanded
Leucippu’s atomic hypothesis.

7. Democritus , dubbed as the
father of atomism, considered
atoms to be solid and
indestructible.
Thought that the universe has
merely atoms and empty space,
which he called the Void

8. Refers to the
philosophy that
states that all
matter was
produced from
atoms.
Atomism

9. He rejected the
idea of
Atomism.
Aristotle (384-322)

10. Aristotole assumed that only the
observable things could be proven
true. Since atoms are not visible to
the naked eye, their presence
could not be confirmed by
observation.

11. He believed that
water, air, fire, and
earth were the
fundamental
elements while hot,
cold, dry, wet were
the four properties
combined to produce
these fundamental
elements.

12. Aristotle also added “ether” as another
fundamental substance.
He believed that ether constitute the
stars, including the sun.
Aristotle also believed that the
seeming empty space is filled with
ether.

13. Belief lasted until the Middle Ages (AD
500-1450) along with the falling out of
support for atomism.
Philosophers that hold on to atomism
were Epicurus and his follower,
Lucretius.
Lucretius wrote a poem entitled “On
the Nature of Things” wherein he
reaffirmed the basic components of
atomism.

14. Unfortunately, the writings were
forgotten after he died and only one
copy of the poem lasted centuries
after.
Ancient Greek philosophers tried to
answer questions about the
composition of matter simply by logic
and reasoning.

15. A substance can be
changed into another
substance. This idea
of changing
substances intitiated
alchemy.
People who practice
alchemy were called
alchemist.
A lchemyA

16. Alchemist learned numerous chemical
substances.
They had shown how certain types of
chemicals react when combined with
other substance.
Thus, alchemist improved the
understanding of basic chemistry.

17. Alchemist were mainly skillful with
metals, creating cheaper imitations of
gold and silver.
Through time, alchemist eventually
believed that consuming transmuted
gold is the secret to immortality, thus
calling it the “Elixir of Life or the
Philosopher’s Stone”

18. •Alchemical process lead to the
discovery of caustic alkalis such as
sodium hydroxide (NaOH) and
ammonium salts.
•The process of “distillation” was also
refined because of alchemy.

19. During the renaissance, one of the most
forceful men of that time, Paracelsus (1493-
1541) founded the school of iatrochemistry
(medical chemistry).
This led to the production of metallic
medicines to cure illness thus encouraging
alchemist to prepare drugs instead of
transmuting metals to gold.

20. He also coined the term “alcohol”
to spirits of wine.
By late 18th century, traditional
alchemy was fully separated from
chemistry.

21. •In a sheet of paper, write a short
essay on how the ancient
discoveries in science been useful
today.
(Provide real examples of studies or
any breakthrough in Science.)