Download - 1.5.1 History of the Atomic Theory (Howell)
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
1/19
Mrs. Howells Grade 9 Science: Acton District High School
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
2/19
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1903AD1898AD1897AD 1911AD 1922AD Beyond
http://www.louisville.edu/provost/wroffice/bulb.gif -
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
3/19
The idea started around..
About 450 BC
The Greek philosopher
Empedocles
stated that matter
consists of fourelements
-earth, air, fire & water-
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1903AD1898AD1897AD 1911AD 1922AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
4/19
But about
About 400 BCThe Greek philosopher
Democritus
developed the firstatomic hypothesis.
- Al l matter be subd iv ided
on ly to a certain poin t , at
which on ly atoms remain.
Atomos- Greek wordfor indivisible
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1903AD1898AD1897AD 1911AD 1922AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
5/19
Unfortunately...
About 350 BCThe Greek philosopher
Aristotle
opposed Democritus' ideaof atoms and dismissed itas worthless and promoted
the 4 element model.Because of Aristotles great
influence in the scienceworld, this concept about
matter lasted for more than2000 years.
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1903AD1898AD1897AD 1911AD 1922AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
6/19
A.D. 500-1600
Arabian, Chinese andEuropean
Alchemists
studied matter,experimenting withdifferent chemical
substances.They devised the systemchemical symbols.
-but they still used the fourelement system-
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1903AD1898AD1897AD 1911AD 1922AD
http://fyndo.myip.org/http://fyndo.myip.org/ -
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
7/19
A.D. 1650-1700sRobert Boyle
Antoine LavoisierJoseph PriestleyHenry Cavendish
Found that matter such as
air and water were made ofa mixture of pure
substances.Their research promoted theidea of matter being made ofelements and disproved theidea of the four element
system .
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1898AD1897AD 1911AD 1922AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
8/19450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1855AD 1879AD 1898AD1897AD 1911AD 1922AD
1808 A.D.British scientist
John DaltonPictured the atom as a tiny,
indivisible sphere much
like a billiard ball.
Further developed the ideaof atom particles in his
atomic theory .
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
9/19
Dalton's Atomic Theory - 1808
All elements are composed of atoms (indivisible
particles)
All atoms of the same element are identical - in
particular they have the same mass.
The atoms ofone kind of element are different from the
atoms of all other elements - in particular the atoms of
one element have a different mass than those of other
elements.
Atoms are indestructible and retain their identity in
chemical reactions.
Compounds are formed by joining atoms in specific
whole number ratios.
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
10/19
1855 A.D.German scientist
Heinrich GeisslerA glassblower and
inventor of the sealed glass
tubes that pumped out airand discharged electricity
through gases.
-his invention helped leadto the next two atom
discoveries-
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1855AD 1879AD 1903AD1898AD1897AD 1911AD 1922AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
11/19450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1855AD 1879AD 1898AD1897AD 1911AD 1922AD
1879 A.D.British scientist
William CrookesDiscovered as the pressurewas lowered in a electric
gas discharge tube, thenegative end appeared to
emit rays, now known to bea stream of free electrons.
This stream also could push
a tiny windmill in the tube.Discovery of charged
particles and that they had
mass .
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
12/19450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1898AD 1911AD 1922AD
1897 A.D.British scientist
J.J. ThomsonExperimented on the
streams of particles usingmagnets and electric
current and discovered thepieces of atoms we know as
electrons and protons.
- Proposed the raisin bunmodel of the atom. Positive
charged sphere withnegatively charged particles
embedded in it-
1897AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
13/19
1896-1898 A.D.French (Polish) scientists
Henri BecquerelPierre & Marie CurieExperimented with natural
radioactivity.
- Their work and thematerials they discovered
greatly helped the next
proposed model of theatom -
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1898AD 1911AD 1922AD1897AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
14/19
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
15/19
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
16/19450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1898AD1897AD 1911AD 1922AD
1922 A.D.Danish scientist
Niels BohrCame up with experimentalevidence proving thatelectrons exist in energylevels (shells) orbitingaround a positively chargednucleus.
-Orbital electron energyshells -
1932AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
17/19
1932 A.D.English scientist
James ChadwickUsing alpha particlesdiscovered a neutral atomicparticle with a mass close toa proton. What hediscovered was theneutron.
-Discovered the third sub-atomic particle of the atom:the neutron -
450 BC 400 BC 350 BC 500-1600 AD 1808AD1650 AD Late 1700s 1831AD 1879AD 1898AD1897AD 1911AD 1922AD 1932AD
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
18/19
History of the Atomic
Theory(see text pg 82 through pg 85 and 91)
A. Fill in the Blank areas in this table during thelesson or review the presentation on our class
website.
B. Draw the Atom Models of:Dalton J.J. Thomson Rutherford Bohr
Time
Perio
d
Scientists Atomic Model What discovery they
made
Ancien
t
Greec
e
Empedocles
Ancien
tGreec
e
Democritus
A.D.
500-
1600
Alchemists Four element
model
Elements like Zinc,
Bithmuth, Phosphorous,
and Arsenic
1650
-late
1700
Robert Boyle
Antoine Lavoisier
Joseph Priestley
Henry Cavendish
1808 John Dalton
1879 William
Crookes
1897 J.J. Thomson
(Nobel prize
1906)
1911 Ernest Rutherford(Nobel prize
1908)
1922 Niels Bohr
(Nobel prize
1922)
1932 James Chadwick(Nobel prize
1935)
Your task:
Work on filling out the
worksheet on the
history of the atom
table as well as
drawing the examples
of the models of the
atom on the bottom of
the sheet.
And
-
7/28/2019 1.5.1 History of the Atomic Theory (Howell)
19/19
Thank you!