nUCLEAR geeks

Democritus

470=380 bc came up with the idea of atoms, said atom were indectrutible

Arisotle

384-322 Bc, matter is made up of earth, wind, and fire, threw out democritus idea, killed science for 2000 years.

Thomson

1856-1940, discovered the electron. Figured out that protons and electrons are =. plum pudding model

Dalton

(1766-1844) proposed the atomic theory/ reintroduced the idea of atoms , gillard ball theory

Becquerel

1852 - 1908, discovered spontaneous radioactivity, made photographic plates from the ore pitchblende/uranium P

Roentgen

(1845-1923) discovered X-rays, revolutionized medicine and physics P

Rutherford

(1871-1937) conducted the gold foil experiment, discovered the nucleus and proton, neutrons

Marie and pierre curie

(1867-1934 — Discovered lement radium and polunium, , introduced radiation therapy. Nobel Prizes in Physics and Chemistry.

Chadwick

(1891-1974) discovered the neutron

Bohr

(1885-1962) , quantam mechanics, solar system model, discovered how far the electron is from the nucleus VERY FAR

1st periodic table

mendeler

What were elemets thought to be made of in the 1860s

Indivisble spheres

How did many scientists in the 1800s think particles were different from one another

they were built of smaller particles

What is emitted through a cathode ray tube , and how can you deflect these ————

electrons , deflected through a magnet

Other than magnets, what can you use to bend a stream of electrons

battery

An electron is _____ a neutron/proton

1/2000th

What did rutherford use to explore the structure of an atom

radioactive particles

If the atom has been exactly as thomson had described, what should the beam of particles should have done?

go through the foil

What unexpected thing happred that suggested thomson was not correct

Some of them came back

Why did some of the alpha particles shot at the gold not pass through

it hit the nuclus

rutherford and chadiwck

neutrons

atoms remade u[p of

empty space

Why dont we identiy elements based on electrons

they come and go

Why dod leements and groups have similar chrmical properties

same number of valence elctrins

When are atoms most stablr

full outside shell — the group 18 has this and are noble gases, they are inert (not moving), helium is a noble gas (full outside shell)