history of the atom

2. All matter is composed of extremely small particles called atoms
7. matter is composed of discrete units called atoms, as opposed to the obsolete notion that matter could be divided into any arbitrarily small quantity
8. said the atom is mostly empty space, with nearly all of its mass concentrated in a tiny central nucleus
10. proposed a theory for the hydrogen atom, based on quantum theory that some physical quantities only take discrete values
11. He said the four elements were not composed of atoms but were continuous forms of matter
13. Said the building blocks of matter atomos, meaning literally “indivisible,”
14. a given chemical compound always contains its component elements in fixed ratio (by mass) and does not depend on its source and method of preparation.
15. when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.

1. the first plural attempt to explain life and change and was based on the combination of four different roots that give rise to life and matter
3. a theory of the nature of matter:
4. He proposed a model of the atom in which negative electrons are scattered throughout a sphere of positive charge
5. represents atoms containing a nucleus of protons and neutrons and a vague gradient or cloud surrounding it containing the ele
6. the electrons were embedded in a uniform sphere of positive charge, like blueberries stuck into a muffin
9. said the atom is mostly empty space, with nearly all of its mass concentrated in a tiny central nucleus
12. the atom consists of a nucleus surrounded by orbiting electrons