Notes: Atomic Models
Democritus
≈380 BC
Dalton
Rutherford Wave Model
≈1800AD
Thompson
≈1930
Bohr
1. Democritus
a. Matter consists of invisible particles called ______________________
b. ______________________ are indestructible
c. Atoms are ______________________, but ______________________
d. Atoms are _______________________________
e. Atoms differ in __________________, ___________________, position and arrangement.
2. Dalton
a. Called the “Billiard Ball Model”
b. Elements are __________________ substances. Elements are made of ____________.
c.
Atoms are _____________________ and _________________________.
d. Atoms of the same element are ______________________.
e. Atoms of different elements are ______________________.
f. ______________________ are formed by joining atoms of 2 or more elements in a
______________________.
3.
Thompson
a. Called the “Blueberry Muffin Model”
b. ______________________ charged particles scattered in a positively charged substance.
c. Called these particles ______________________.
d. The atom is ______________________ (means it can be broken into smaller particles).
4.
Rutherford
a. Atom is mostly ______________________.
b. There is a small, hard ______________________ at the center of an atom.
c. The ______________________ is a positively charged particle
5.
Bohr
a. Called the “Planetary Model”
b. Electrons ______________________ the nucleus like planets orbit the sun.
c. These different layers are called ______________________ or ______________________.
6. Schrodinger
a. Part of the “Wave Theory”
b. The atom is not flat, it is 3-dimensional, or round like a ______________________.
c.
Electrons move at the speed of ______________________.
d. The area outside the nucleus where electrons fly around is called the
______________________
e. Since atoms are electrically neutral, and a proton is positive and an electron is negative, then
there must be one ______________________ for every ______________________.
7. Chadwick
a. There is another particle in the nucleus. It is electrically neutral and is called a
______________________.
b. The number of protons in the nucleus determines what element it is. This number is called the
______________________.
Directions: Place an “X” in the box that shows what each scientist believed.
Indivisible
Democritus
Dalton
Thomson
Rutherford
Bohr
Schrodinger
Electron
Nucleus
Orbit
Electron Cloud
Notes: Atomic Models
Democritus
≈380 BC
Dalton
Rutherford Wave Model
≈1800AD
Thompson
≈1930
Bohr
1. Democritus
a. Matter consists of invisible particles called _____Atomos_____
b. _______Atomos_________ are indestructible
c. Atomos are ____solid________, but ______indivisible____
d. Atomos are ____homogeneous____
e. Atomos differ in ____size___, ___shape___, ___mass___, position and arrangement.
2. Dalton
a. Called the “Billiard Ball Model”
b. Elements are ___pure___ substances. Elements are made of ___atoms_____.
c.
Atoms are _____indivisible____ and _____indestructible____.
d. Atoms of the same element are ____exactly alike___.
e. Atoms of different elements are ____different______.
f. ___Compounds___ are formed by joining atoms of 2 or more elements in a ____constant ratio
ex: H2O is a 2:1 ratio___.
3.
Thompson
a. Called the “Blueberry Muffin Model”
b. ____Negatively___ charged particles scattered in a positively charged substance.
c. Called these particles ____electrons____.
d. The atom is ____divisible!____ (means it can be broken into smaller particles).
4.
Rutherford
a. Atom is mostly _____empty space_____.
b. There is a small, hard _____nucleus____ at the center of an atom.
c. The ____proton____ is a positively charged particle
5.
Bohr
a. Called the “Planetary Model”
b. Electrons ____orbit____ the nucleus like planets orbit the sun.
c. These different layers are called ___energy levels___ or ____orbital shells___.
6. Schrodinger
a. Part of the “Wave Theory”
b. The atom is not flat, it is 3-dimensional, or round like a ___sphere or ball___.
c.
Electrons move at the speed of ____light - and never stay still!___.
d. The area outside the nucleus where electrons fly around is called the ____electron cloud___
e. Since a proton is positive and an electron is negative, and atoms are electrically neutral, then
there must be one ___proton___ for every ___electron____.
7. Chadwick
a. There is another particle in the nucleus. It is electrically neutral and is called a
____neutron____.
b. The number of protons in the nucleus determines what element it is. This number is called the
____atomic number____.
Indivisible
Democritus
X
Dalton
X
Electron
Nucleus
Orbit
Thomson
X
Rutherford
X
X
Bohr
X
X
X
Schrodinger
X
X
X
Electron Cloud
X