quiz 1 again? Flashcards
(12 cards)
who is democritus (greek)
he said matter can be divided into smaller parts called atomos
who is Aristotle (greek)
he said that matter is fire, water, earth, air
How did Philosophers in 400BCE come to their conclusion
no experiments, just observations and reason
what were alchemists
transformed metals into gold, some chemical processes still used today
Who is John dalton
Atoms are solid, indestructible spheres = “Billiard ball model”
Atoms of one element are identical, but different from those of other elements
Atoms can combine (get rearranged) form new substances (molecules!)
Who is JJ Thompson
founded the electron. Atoms are solid spheres with a
positive core embedded with
negative particles = “Plum
pudding” model
(raisin bun/ blueberry muffin)
Who is rutherford
performed gold foil experiment. discovered nucleus and surrounded by electrons in its empty space
who is Chadwick
found out neutrons have no charges and has the same mass as protons
who is nile’s bohr
energized atoms release light of specific colours when seen through a prism. Proposed electors orbit the nucleus in definite energy levels
who is erwin schrödinger
made quantum mechanical model based on mathematical calculations (electron cloud model) Used by almost everyone today. Electrons are found in 3D regions or clouds around nucleus, denser cloud is higher electrons1
Modern Atomic theory
- All matter is made up of atoms and those are made up of subatomic particles
- Atoms of an element cannot be converted into atoms of another element through chemical reaction
- Atoms of one element share the same properties
- Atoms of different elements combine specific proportions to form compounds
How is the standard atomic notation formed
Mass number, chemical symbol, atomic number
