Developmen

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

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.

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.

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.

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.

Leucippus is considered as

the first atomist but is less

well known compared to

Democritus who expanded

Leucippu’s atomic hypothesis.

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

Refers to the

philosophy that

states that all

matter was

produced from

atoms.

Atomism

He rejected the

idea of

Atomism.

Aristotle (384-322)

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.

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.

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.

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.

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.

A substance can be

changed into another

substance. This idea

of changing

substances intitiated

alchemy.

People who practice

alchemy were called

alchemist.

A lchemyA

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.

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”

•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.

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.

He also coined the term “alcohol” to spirits of wine.

By late 18th century, traditional alchemy was fully separated from chemistry.

• 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.)