atomism.pptx

atom is the smallest unit of matter

1. Atomos, Aristotle and Alchemy (Chemistry Before Modern History)

2. At the end of the lesson, the learners will be able to: Discuss key developments in the concept of the atom and element throughout pre-modern history 2. Discuss key developments in the practical application of chemistry throughout pre-modern history. 3. Articulate the contributions of alchemy as a protoscience to chemistry. Specific Learning Outcomes

3. I can describe the ideas of the Ancient Greeks on the atom. b. I can describe the ideas of the Ancient Greeks on the elements. c. I can describe the contributions of the alchemists to the science of chemistry.

4. Leucippus and Democritus Jabir Ibn- Hayyan (Geber) Atomism Alchemy Aristotle Protoscience

5. Atomism, non-atomistic views of the Greeks, the growth of alchemy across different civilizations, Western Alchemy

6. Greek philosophers who began considering the nature of what things were made of. preoccupied with how the universe seemed to be both changing and constant.

7. Leucippus and Democritus were two of the most important theorists about the natural and physical world. They were called physicists in Ancient Greece. They considered the idea of atomism , or the idea that things are made up of much smaller things that cannot be changed nor divided.

8. Among the features of their theory were the following: Atoms make up most of the things in the universe; where there are no atoms, there is a void. • Atoms are incredibly small and cannot be divided, hence atomos (uncuttable). • Atoms themselves are solid, homogeneous and cannot change. • Atoms moving about and colliding in the void cause the changes we see in our universe. • The shapes, sizes and weights of individual atoms influence the characteristics of the thing they make up; e.g. sharp atoms cause our tongues to tear and make bitter or sour tastes, and atoms that compose clay are joined by flexible joints which harden when the clay is baked.

9. Atomism , although more a philosophical idea than a scientific one was closest to our current thinking about matter. Despite having advocates, atomism was set aside because more prominent philosophers opposed it. Religious groups later declared it as heretical or blasphemous because they deemed atomistic thinking denied the existence of God.

10. Atomism, although more a philosophical idea than a scientific one was closest to our current thinking about matter. Despite having advocates, atomism was set aside because more prominent philosophers opposed it. Religious groups later declared it as heretical or blasphemous because they deemed atomistic thinking denied the existence of God.

11. Some of the ideas that served as arguments against atomism and what this revealed about how the Greeks thought about matter and the world:

12. • The philosopher Anaxagoras argued that there was an infinite number of elementary natural substances in the form of infinitesimally small particles that combined to comprise the different things in the universe.

13. • Another theory by a philosopher named Empedocles stated that everything is made up of four eternal and unchanging kinds of matter, fire, air (all gases), water (all liquids and metals) and earth (all solids).

14. • The well-known philosopher Plato further expanded Empedocles’ theory by saying each of the four kinds of matter is composed of geometrical solids (the “Platonic solids”) further divisible into triangles. When rearranged, these triangles could cause the apparent transformations between the four basic kinds of matter.

15. Aristotle , on the other hand, believed that the four elements could be balanced in substances in an infinite number of ways, and that when combined gave proportions of “essential qualities,” hot, dry, cold and wet. Transformations between the four elements (or changes in their balance in a substance) caused changes in the universe.

16. it was an obsession with Aristotle’s ideas (and his arguments against atomists) that prevented atomism from gaining ground.

17. Our concept of matter didn’t advance much during this time, the practical aspect of dealing with substances, matter and materials flourished in different civilizations before and after the Greeks:

18. • The Mesopotamians had techniques to utilize metals like gold and copper. They even assigned certain symbols to match metals with the heavenly bodies such as the Sun and Moon. They also made use of other materials such as dyes, glass, paints, and perfumes.

19. • The Egyptians adapted techniques from the Mesopotamians and perfected the use of bronze, dye and glass that the Greeks later copied.

20. • The Chinese also had their own processes for metalwork and ceramic materials, but they especially focused on finding minerals, plants and substances that could prolong life. Some of the substances discovered in Chinese medicine have been found to have actual positive effects while others were found useless or even harmful, like mercury.

21. • The Indians, like the Chinese, had a kind of alchemy ( rasayana ) that looked at different substances and practices for Vedic medicine. This is tied closely to Hindu and Buddhist beliefs. They also perfected the use of iron and steel and were well-known manufacturers of dyes, glass, cement, solutions for textiles, and soap.

22. The Arabs and Muslims enriched not only the practice but also the literature of chemistry. In particular, the scholar Jabir Ibn- Hayyan , also known as Geber, translated the practices and Aristotelian thinking of the Greeks and wrote extensively on how metals can be purified. He came up with the preparation of acids such as nitric, hydrochloric and sulfuric acids, as well as aqua regia (nitro-hydrochloric acid).

23. Despite many of the progress being practical, much of it was shrouded in mysticism or cultural beliefs, and was often a result of trial and error. These advances in materials, metallurgy and medicine would often be collectively referred to in history as alchemy , from the Arabic/Greek alkīmiyā or “the art of transmuting.”

24. The field of alchemy became popular in the Western world because of Aristotle’s ideas on the elements and the techniques developed by other civilizations. Alchemists tried to play with the balance of the four elements (fire, water, air, earth) and three principles (salt, sulfur and mercury) to transform or transmute substances. Among their aims was to try and transform “impure” or “base” metals like lead or iron into the “purer” metals of silver or gold, discover a magical “Philosopher’s Stone,” and produce the so-called “Elixir of Life.” With a T-chart, distinguish how alchemy both contributed to and hampered scientific thought.