Unit 2: Atoms and Molecules Flashcards
1
Q
basic particle of chemical elements
A
atom
2
Q
consists of a nucleus protons and neutrons, surrounded by an
electromagnetically-bound swarm of electrons.
A
atom
3
Q
nucleus is made up of
A
proton + neutron
4
Q
subatomic particles of an atom
A
protons
neutrons
electrons
5
Q
atomic model and theory timeline
A
democritus
john dalton
jj thomson
ernest rutherford
niels bohr
erwin schrodinger
james chadwick
modern
6
Q
- matter was made of small, hard particles called atoms (atomos)
- indivisible
- proposed that matter could not be divided into smaller pieces forever
A
democritus
7
Q
- created the very first atomic theory known as the Billiard Bell
- viewed atoms as tiny, solid balls
- matter is made up of atoms
A
john dalton
8
Q
- raisin bread model/plum pudding
- he showed that the atom was made of even smaller things
- discovered Electrons (with Cathode Ray Tube)
A
jj thomson
9
Q
- discovered protons gold foil or alpha scattering experiment by using radium
- discovered protons and the nucleus
- he discovered that atoms have (+) particles in the center, and are mostly empty space
A
ernest rutherford
10
Q
- planetary model
- nucleus is = to protons + neutrons
- nucleus is surrounded by electrons
- improved on rutherford’s model
- proposed that electrons move around the nucleus in specific layers, or shells
A
niels bohr
11
Q
- quantum mechanical model
- electron cloud model
- estimates the probability of finding an electron in a certain
position
A
erwin schrodinger
12
Q
- discovered neturons
- working with rutherford, he discovered particles with no charge, these were called as neutrons
A
james chadwick
13
Q
- work done since 1920 has changed the model
- the new atomic model has electrons moving around the nucleus in a cloud
A
modern
14
Q
atomic #
A
protons = electrons
15
Q
mass #
A
electrons + neutrons
protons + neutrons
