Science 8 - Atomic Theory and Atomic Models.pdf

Atomic Theories and Atomic Models

1. 1

2. Describe the different atomic
models proposed by scientists;

Arrange the development of
atomic models in chronological
order;

Compare and contrast the
contributions of Dalton, Thomson,
Rutherford, and Bohr; and

Appreciate the importance of the
atomic model in understanding ,
matter.

3. ATOMIC
MODELS

Solid Sphere Model
Plum Pudding Model
Nuclear Model
Planetary Model

Quantum Model

4. Y CF

一
WHAT DO YOU ALREADY +)
KNOW ABOUT ATOMS?”

o a “a

QUESTION

5. SCIENTISTS CREATED MODELS
OF ATOMS. THESE MODELS
CHANGED OVER TIME AS NEW

DISCOVERIES WERE MADE.”

ANSWER

6. ps | 一 一

aie i
Thomson's Model of the Atom 4

Dalton’s model of atom (1803)

- >
4
| >

7. \
Bohr mode

N shell

1

Rutherford Model of the Atom
iC) Nucleus

© Electron

M Shell
L Shell

K Shell
Positively
charged
Nucleus

8. Yo

6 WHATDOYOUNOTICE 」
+ に ABOUT THE DIFFERENCES -一
LU
= & BETWEEN THESE MODELS?

. À

9. JUST LIKE TECHNOLOGY, y

SCIENTIFIC IDEAS IMPROVE E

OVER TIME AS EVIDENCE
INCREASES

ANSWER

10. ATOMIC THEORY TIMELINE

1803 1897 1911

o ©
Solid Plum Nuclear Planetary
Sphere Pudding Ernest Niels
Rutherford Bohr
John Dalton JJ. nec Electrons move in
Thomson quantized, discrete

small, dense, positively
charged nucleus at the
center, with electrons
orbiting around it,
similar to planets
orbiting around the
sun.

energy levels
around the nucleus
and emit or absorb
energy when
transitioning 10
between levels.

11. JOHN DALTON > ーー

1766 - 1844 e

ㆍ British chemist and physicist
* Proposed the Solid Sphere Model in the
early 19th century

« Shifted from philosophical ideas to scientific theory 7

» First atomic model based on experimental evidence and
quantitative observations

・ Paved the way for the development of modern atomic theories, |

W À ww W )

12. \
\
à

Atoms are tiny balls that can't be
SOLID broken and are all made of the same
SPHERE material. This theory helped explain how
MODEL | different chemicals mix together and
what makes them different.

U EEE

° Couldn’t explain differences in atomic mass within an
element (isotopes)

« Didn’t account for the presence of subatomic particles
like protons, neutrons, and electrons

+ Couldn't explain the behavior of atoms in chemical
reactions

LIMITATIONS

13. •
•
•
•
•
13

14. サリ o 一
Atoms are like plum pudding, with tiny

PLUM positive charges scattered throughout
PUDDING ecloud of negative electrons. This
MODEL theory helped explain why atoms have

a neutral charge overall and why they

emit light when they collide with each —
other. (一

<=

* Couldn’t explain why electrons didn't
collapse into the positive sphere

+ Failed to predict the distribution and 5
arrangement of electrons ( =

・Lacked explanation for the nucleus and its
positive charge =

LIMITATIONS

15. ERNEST RUTHERFORD

1871 - 1937

・ New Zealand-born physicist known for
his contributions to nuclear physics

¢ Introduced the Nuclear Model in the early
20th century

EN

ㆍ Explained the behavior of positively charged alpha
particles in the gold foil experiment

+ Laid the groundwork for understanding atomic
structure and Iadieactivity

/

16. ea
=i) WAR

1911 u:
NUCLEAR <
MODEL Atoms have a nucleus with aV

positive charge and most of the
mass, surrounded by electrons
that orbit like planets.

It explains why particles can
pass through or bounce off
atoms, and is the basis of our
current understanding of
atomic structure. 16

17. NIELS BOHR HER cn ペー
ン 4 mer + Danish physicist

~ e A 부 데이 known for his
^, … 導 ~ ~ ~ L Shell A A 。
aaa pioneering work in

{fy me NON À
/ 1 K Shell A

| | Os atomic structure
\ y) | dass

NN し プン ノ // ナ ・ Proposed the

\ K グ J /
~ ン ン Planetary Model in the
M
Se early 20th century =.
VER

18. PLANETARY
MODEL

1913

Electrons orbit the
nucleus of an atom in
specific energy levels

or shells.

18

19. PLANETARY

MODEL Fer

This theory helped explain
why atoms emit light and
why they absorb certain
colors of light. It also helped
explain the stability of atoms
and why they don't fall apart.

19

20. ATOMIC THEORY TIMELINE

1803 1897 1911

o ©
Solid Plum Nuclear Planetary
Sphere Pudding Ernest Niels
Rutherford Bohr
John Dalton JJ. nec Electrons move in
Thomson quantized, discrete

small, dense, positively
charged nucleus at the
center, with electrons
orbiting around it,
similar to planets
orbiting around the
sun.

energy levels
around the nucleus
and emit or absorb
energy when
transitioning 20
between levels.

21. Y CF

GROUP ACTIVITY: EACH GROUP IS.
ASSIGNED ONE ATOMIC MODEL Ty
(DALTON, THOMSON,

RUTHERFORD, BOHR).

ACTIVITY

( |)

22. ACTIVITY

N
db

(
x
X

u

+
」

GROUP ACTIVITY: MAKE A SIMPLE | >
POSTER OR SKIT SHOWING HOW Ty
THE MODEL EXPLAINS THE ATOM

Lar

더 A

23. C >) KE
Sy
Time to test your knowledge of the =

ATOMIC

u THEORY

24. 1. WHO PROPOSED THAT THE
ATOM IS LIKE A SOLID SPHERE?

QUESTION

Type your response here.

ANSWER

25. 2.WHAT IS THE MAIN IDEA OF
THOMSON’S “PLUM PUDDING
MODEL”?

QUESTION

Type your response here.

ANSWER

26. QUESTION

3. WHICH EXPERIMENT LED
RUTHERFORD TO CONCLUDE THAT
ATOMS HAVE A NUCLEUS?

ANSWER

Type your response here.

27. 4. HOW DID BOHR’S MODEL
IMPROVE RUTHERFORD’S?

QUESTION

Type your response here.

ANSWER

28. 5. WHY IS IT IMPORTANT THA
SCIENTIFIC MODELS CHANGE
OVER TIME?

QUESTION

Type your response here.

ANSWER

29. Make a timeline showing the
evolution of the atomic model
(Dalton > Thomson > Rutherford >

Bohr) in a 1 short bondpaper.

30. 30