For example, regardless of how many times you break a stone in half, the pieces never resemble any of the core elements of fire, air, water, or earth. Stone was thought to contain a high amount of earth, while a rabbit was thought to have a higher ratio of both water and fire, thus making it soft and giving it life.Įmpedocles's theory was quite popular, but it had a number of problems. The ratio of these four elements affected the properties of the matter. Empedocles argued that all matter was composed of four elements: fire, air, water, and earth. Empedocles, a Greek philosopher and scientist who lived on the south coast of Sicily between 492 BCE and 432 BCE, proposed one of the first theories that attempted to describe the things around us. Then they gave these things the names, such as 'fur,' 'stone,' or 'rabbit.' However, these people did not have our current understanding of the substances that made up those objects.

Understanding Scientific Journals and ArticlesĮarly humans easily distinguished between materials that were used for making clothes, those that could be shaped into tools, or those that were good to eat.

Using Graphs and Visual Data in Science.Scientists and the Scientific Community.Scientific Notation and Order of Magnitude.The Case of the Ivory-billed Woodpecker.Santiago Ramón y Cajal and Camillo Golgi.Factors that Control Earth's Temperature.Plates, Plate Boundaries, and Driving Forces.

Solutions, Solubility, and Colligative Properties.

Y-Chromsome and Mitochondrial DNA Haplotypes.Absorption, Distribution, and Storage of Chemicals.

What is matter made of