How Rutherford Discovered the Nucleus: One of science’s greatest experiments!

Slides:

Advertisements

Similar presentations

Democritus Dalton 3. JJ Thomson 4. Rutherford 5. Bohr 6. Chadwick

Advertisements

BELL RINGER What are the three subatomic particles? (Things smaller than an atom, you learned in 8 th grade)

CHEMISTRY 161 Chapter The Early Atomic Theory pure substances compounds elements combine different elements H 2, O 2 H 2 O [O 3 ] John Dalton.

Theories and Structure of the Atom. Dalton’s Atomic Model (1805) Dalton’s model of the atom was an indivisible sphere of matter. Dalton’s Contributions:

Chapter 4 Atomic Structure

Rutherford’s Gold Foil Experiment

The Gold Foil and the Nucleus

ERNEST RUTHERFORD & THE GOLD FOIL EXPERIMENT By Jake Easton & James Lampmann.

( Rutherford’s experiment ).  Before 1910, the structure of the atom was thought to correspond with the « plum pudding model ». In summary, the Plum.

Structure of the Nuclear Atom

Chapter 4: Discovery of Atomic Structure. Prentice Hall © 2003Chapter 2 The Discovery of Atomic Structure An ancient Greek named Democritus was the first.

Science Starter: Black Boxes Groups of 2: Manipulate the box so the marble moves around the fixed object inside of the box. DO NOT OPEN THE BOX Discuss.

The History of the Atomic Model In other words, the old guys who came up with the atom.

Rutherford Experiment and Atomic Structure

Subatomic Particles Dalton, Democritus & other early chemists thought the atom was a homogeneous particle. Static electricity between objects made scientists.

J.j. Thomson Atomic Model

EARLY Atomic theories.

The History of the Atom…. went against, Aristotle, who believed that matter was composed of four qualities: earth, fire, air and water all matter is composed.

History of Atomic Structure Atoms: their parts & pieces.

Section 2: Atomic Discoveries

For each scientist you need to know  Approximate date of discovery  Discovery  Experiment/Theory  Atomic Structure from their perspective FOCUS.

Atomic Theory. The Atom Recall the atom is the smallest particle making up an element.

Atomic Theory 15,000 kilotons.  Dismissed idea of the atom. Early Greeks Two schools of thought:  Matter is made of indestructible particles called.

Early Experiments to Characterize the Atom 2. 4 Chapter 2 Atoms, Molecules, and Ions.

< BackNext >PreviewMain Section 1 Development of the Atomic Theory The Beginning of the Atomic Theory What Is an Element? Around 440 BCE, a Greek philosopher.

The Atomic Theory 1.Atomic Theory Matching 2.Atom Size 3.Democritus 4.Dalton – Ball Model 5.J.J. Thompson – Raisin Bun Model 6.Rutherford – Gold Foil Experiment.

Chapter 3 Atoms: The Building Blocks of Matter. Objectives: Students should be able to: Summarize the essential points of Dalton’s atomic theory. Describe.

History of Atomic Structure Atoms and their parts.

Section 4.2 Defining the Atom.

Atomic Models Lesson 2 Rutherford’s Model. Gold Foil Experiment Rutherford was attempting to lend support to Thomson’s atomic model by sending a beam.

Rutherford’s alpha scattering experiment. source of alpha particles thin gold foil photographic film beam of  particles most pass straight through 1 in.

Rutherford’s Gold-Foil Experiment

Rutherford’s experiment Day 2. Last time Discussion of early atomic model- the plum pudding model To refresh your memory: – Large slightly positive mass.

Ch. 4.2 Structure of the Nuclear Atom

Ernest Rutherford By Mania Sehgal, Catherine Cincotta, Alec Tripodi.

3-2 Radioactivity and the nucleus (10.2 pg )

THE ATOM! BUILDING BLOCKS OF MATTER. Rutherford! ► The gold foil experiment ► Shot alpha particles (helium nuclei) at gold foil 4 Mass number charge 2+

Models of the Atom. Objectives Recognize that science is a progressive endeavor that reevaluates and extends what is already known. (SPI Inq.1)

The scattering experiment.  The scattering experiment.

Atomic Structure.

Ernest Rutherford (Nelson, New Zealand).

Part 2: Rutherford and the Gold Foil Experiment

1 Chapter 4 Atoms and Elements 4.3 The Atom Basic Chemistry Copyright © 2011 Pearson Education, Inc.

John Dalton’s Atomic Theory  Elements composed of small particles called “atoms”  All atoms of a given element are the same, but different from other.

The Changing Model of the Atom

Roy Kennedy Massachusetts Bay Community College Wellesley Hills, MA Introductory Chemistry, 2 nd Edition Nivaldo Tro Chapter 4 Atoms and Elements 2006,

Atomic Structure Where our ideas of the atom come from and what we know now.

23.1 Atomic structure The Rutherford scattering experiment  In 1911, Ernest Rutherford carried out the famous Rutherford scattering experiment to explore.

Historical Development of an Atom. Democritus B.C Democritus was a Greek philosopher ( B.C.) who is the father of modern atomic thought.

Atomic Theory Review. Question 1 Which of the following statements is not associated with Dalton's Atomic Model? a)All matter is composed of very small,

THE STRUCTURE OF THE ATOM.  All atoms consist of 2 regions:  1) Nucleus: very small region located near the center of the atom  Proton: positively.

The Changing Model of the Atom From Democritus to Bohr.

Atomic Structure Section 4-1. Democritus Greek philosopher 4 th Century BC First to come up with “atom”. Matter is composed of tiny particles called atoms.

DEVELOPMENT OF THE ATOMIC THEORY Atom- smallest particle into which an element can be divided and still be the same substance Called the building blocks.

Development of the Atomic Theory Chapter 4 - Section 1 p Vocabulary: 1.atom 2.Electron 3.nucleus 4.electron cloud.

The Changing Model of the Atom. Aristotle 400 BCE claimed that there was no smallest part of matter different substances were made up of different proportions.

By the end of this presentation, you should be able to: demonstrate a qualitative understanding of the  - particle scattering experiment and the evidence.

Thomson Model – The ‘plum pudding’

The Roach in the Pudding

Lesson 2 Rutherford’s Model

By the end of this presentation you should be able to……

ATOMIC HISTORY & ISOTOPES

Chapter 3- Atomic Structure

History of the Development of the Modern Model of the Atom

Chapter 3 Experiments of Thomson and Millikan

THE ATOMIC NUCLEUS How is the atom put together?

Rutherford’s Atomic Model

Tro's "Introductory Chemistry", Chapter 4

Atomic Theory Model A familiar idea used to explain.

Presentation transcript:

How Rutherford Discovered the Nucleus: One of science’s greatest experiments!

 Rutherford used the ideas of radioactivity to carry out experiments to help him better define the atomic model.  His experiment involved: Exploring matter by shooting radioactive alpha particles against thin sheets of metal. Rutherford’s Atomic Model

Radium in Lead Block Alpha Particle beam Fluorescent Screen Thin sheet of Gold foil Fluorescent Screen A FEW particles are sharply deflected MOST particles passed through the gold foil & were not deflected SEVERAL particles pass through the gold foil & were slightly deflected

Conclusions from Rutherford’s Experiment: 3 Main Observations OBSERVATIONSCONCLUSIONS 1. MOST (almost all) went through the gold foil & were not deflected Atom contains a significant amount of empty space 2. FEW (not many) bounced directly back The atom’s dense core (nucleus) must be very small 3. SEVERAL (some) passed through the gold foil & were deflected The nucleus must be positive (law of repulsion) Alpha Particles MOST went through empty space FEW approach nucleus & bounced back SEVERAL were deflected by the nucleus Gold Atom

Rutherford Model Rutherford proposed a new model based on his findings and Thomson's Model. Rutherford’s Model placed electrons orbiting, like a cloud, around a dense, positively charged nucleus. Electrons Nucleus

Rutherford’s famous gold foil experiment is shown below. Which of the four statements stated are true and which are false? (there can be more than one true!) Lead Gold Florescent Screen Lead Box (Radio active substance ) 1.Since most of the alpha particles went through the gold foil, the atom consists of mostly of empty space. 2.All of the alpha particles are deflected because they repel the electrons 3.Most of the alpha particles bounce straight back showing that the nucleus is very large. 4.Several of the alpha particles are deflected showing that the nucleus must have a positive charge

 Rutherford’s Model Be familiar with diagram of experiment Know experiment results:  Particles go through - mostly empty space  Particles slightly deflected - same charge as nucleus so repelled  Particles bounced back- direct hit on nucleus