2. Background

Lived from September 6, 1766
– July 27, 1844

English chemist, Meteorologist,
And Physicist.

Born into a Quaker family at
Eaglesfield in Cumberland,
England.

At age of 15 helped his older
brother run a Quaker school in
nearby Kendal

Dalton was heavily influenced
in early life by Elihu Robinson,
who was a meteorologist and
instrument maker. This got him
started into mathematics and
meteorology.

3. Contributions

Color blindness- He lead a lot of
research in the area of color blindness
and because of it the common term for
color blindness became “Daltonism” in
his honor.

He was one of the first to even formally
publish about color blindness at the
time.

He followed this essays with many on
different topics such as reflection and
refraction of light.

(Fun Fact): He Himself was color blind

Daltons law- The law of partial
pressures.
Statue of Dalton in
Manchester Town Hall

4. Contributions (cont.)

Daltons Atomic Theory

This theory had five main points

The atoms of a given element are different from those of any other element; the
atoms of different elements can be distinguished from one another by their
respective relative atomic weights.

All atoms of a given element are identical.

Atoms of one element can combine with atoms of other elements to form chemical
compounds; a given compound always has the same relative numbers of types of
atoms.

Atoms cannot be created, divided into smaller particles, nor destroyed in the
chemical process; a chemical reaction simply changes the way atoms are grouped
together

Elements are made of tiny particles called atoms.

5. Justice
 He didn’t actually find or figure out
color blindness he just built off other
peoples work and did research but it
still became commonly known as
“Daltonism”
 He also didn’t come up with the
base of most of his theories for
example “Daltons law” (law of
Partial Pressures) was really based
off Charles’s law (Gay-Lussac’s law)

7. Early
Childhood

Faraday was born in
1791

Grew up near London in
slums known as
Newington Butts

His father was a
blacksmith

Family was poor

Had very little education

Physically weak

8. fe as A book Binder

Physical handicap led him to bookbinding

Apprentice to master Georges Reibau

Reading and bookbinding

Encyclopedia Brittannica and Conversations on
Chemistry

Successor Of Sir Humphry Davy

9. Discoveries

Electromagnetic Induction

Electrical field and electrical currents

How could he continuously create this phenomena?

10. Importance Of His
Discoveries

The electric generator allowed for electric energy to
be produced without the consumption of chemical
energy

Using turbines to produce electricity

Using water, steam, coal, oil, wind to power turbines

Electricity on a larger scale

13. Introduction
 Sir Joseph John "J. J."
Thomson (18 December
1856 – 30 August 1940) was
a British physicist and Nobel
laureate.
 He is credited with
discovering electrons and iso
topes, and inventing the
mass spectrometer.
 Thomson was awarded the
1906 Nobel Prize in
Physics for the discovery of
the electron and for his work
on the conduction of
electricity in gases.

14. What Did He Prove?
 Thomson, in 1897, was the first to suggest that the
fundamental unit was over 1000 times smaller than
an atom, suggesting the sub-atomic particles now
known as electrons. Thomson discovered this
through his explorations on the properties of cathode
rays.

15. Picture of Cathode Ray
Experiment

16. His Other Works
 In 1905 Thomson discovered the
natural radioactivity of potassium.
 In 1906 Thomson demonstrated that hydrogen had
only a single electron per atom. Previous theories
allowed various numbers of electrons.

17. Awards
 Royal Medal (1894)
 Hughes Medal (1902)
 Nobel Prize for Physics (1906)
 Elliott Cresson Medal (1910)
 Copley Medal (1914)
 Franklin Medal (1922)

19. Introduction
 Eugen Goldstein
(September 5, 1850 –
December 25, 1930) was a
German physicist. He was
an early investigator of
discharge tubes, the
discoverer of anode rays,
and is sometimes credited
with the discovery of the
proton.

22. Background
 Born: October 20 1891
 Died: July 24 1974
 Orgin: Bollington, Cheshire,
England
 Proffesor of physics at
University of Liverpool in 1935

23. Education
 Chadwick attended Manchester high school,
he graduated from the Honours School of
Physics in 1911. He spent two years under
proffesor Rutherford in the Physical
Laboratory in Manchester were he worked on
radioactivity problems and gained his M.sc
degree in 1913.

24. Discoveries
 He discovered the neutron
 He also discovered the nucleus of the atom
Theories
James Chadwicks’ theory that electrons rotate around the nucleus in
Disproven
defintie pathes was disproven
Electrons actually form a cloud around the nucleus

26. In what period of time did he live and
what is his country of origin?
August 30,
1871and he died on October
19, 1937 in Brightwater,
New Zealand.
 …Rutherford born on

27. When did he conduct his experiment?

He conducted his experiment on………
1911by Hans Geiger and Ernest Marsden at the suggestion of Ernest
Rutherford. Geiger and Marsden expected to find that most of the
alpha particles travel to straight trough the foil with little deviation,
with a remainder being deviated by a percent or two.

28. What was he trying to prove w/ his
experiment?
 Rutherford proving about the existence of ……..
Neutrons. It was named by James Chadwick.
 Which could somehow compensate for the repelling
effect of the positive charges of protons by causing an
attractive “nuclear force” and thus keep the nuclei
from flying apart from repulsion between protons.

29. Summarize his experiment (what he did
and what he discovered)
Gold Foil Experiment

30.  The gold foil experiment consisted of a series of
tests in which positively charged alpha particles
(helium nuclei) were fired at a very thin sheet of
gold foil. If Thomson's Plum Pudding model was to
be accurate, the big alpha particles should have
passed through the gold foil with only a few minor
deflections. This is because the alpha particles
are heavy and the charge in the "plum pudding
model" is widely spread.

31.  In detail, a beam of alpha particles, generated by
the radioactive decay of radon, was directed normally
onto a sheet of very thin gold foil in an evacuated
chamber. A zinc sulfide screen at the focus of a
microscope was used as a detector; the screen and
microscope could be swivelled around the foil to
observe particles deflected at any given angle. Under
the prevailing plum pudding model, the alpha particles
should all have been deflected by, at most, a few
degrees; measuring the pattern of scattered particles
was expected to provide information about the
distribution of charge within the atom.

32. Why was he surprised by his
experimental results?
 Bec. On his experiments, many of the alpha particles
did pass through as expected, many others were
deflected at small angles while others were reflected
back to the alpha source.

33. How did his results fit w/
Thomson’s view of the atom?
 Since none of Thomson's negative "corpuscles"
(i.e. electrons) contained enough charge or mass to
deflect alphas strongly, nor did the diffuse positive
"pudding" or cloudlike positive charge, in which the
electrons were embedded in the plum pudding model.
Instead, Rutherford suggested that a large amount of the
atom's charge and mass is instead concentrated into a
very physically small (as compared with the size of the
atom) region, giving it a very high electric field. Outside of
this "central charge" (later termed the nucleus), he
proposed that the atom was mostly empty space.

34. Describe his model of the
atom
a number of tiny electrons circled the nucleus like the particles then hypothesized to make up the
ring around Saturn. By implication, Rutherford's concentration of most of the atom's mass into a
very small core, made some type of planetary model an even more likely metaphor than before, as
such a core would contain most of the atom's mass, in an analogy to the Sun containing most of
the solar system's mass.

35. WERE His beliefs accepted
by the society at that time?
 His beliefs were accepted until one scientist made an experiment
regarding Rutherford’s experiment. He is Niels Bohr.

37. Born On : 7th October 1885
Death : 18th November 1962
Nationality : Danish
Field : Physics

38. In 1912
he married his wife,
Margrethe Norlund. He had six
childeren, two of them died.
One of their sons, Aage Bohr
grew up to be an important
physicist who recieved the
Nobel Prize in 1975.

39. In 1912 he met and later joined
Ernest
Rutherford at Manchester University.
In 1922, Bohr was awarded the Nobel
Prize in physics.
Bohr had adapted Rutherford's
nuclear
structure .

40. Bohr model of the atom(part I)
1.The electrons can only travel in certain
orbits.
2.The electrons of an atom revolve around
the nucleus in orbits.
Bohr model of the atom(part II)
Bohr introduced the idea
that an electron could drop
from a higher-energy orbit
to a lower one, in the
process emitting a
photon(light quantum) of
discrete energy.

41. Thank You =‘)