Atomic Theories Chapter 4.1 How do we know about atoms when no one has ever seen inside an atom?

Slides:

Advertisements

Similar presentations

History of the Atom.

Advertisements

Chapter 4 Atomic Structure

Atomic Theories.

The History of Atomic Theory A piece by piece progression through the structure of the atom.

Models of the Atom: A Historical Perspective

Democritus: The Atom (around 400 BCE)

The History of Atomic Theory

History of the Atomic Theory

History of Atomic Theory

History of Atomic Theory 1

The History of Atomic Theory

AIM: Models of the Atom DO NOW:

The History of Atomic Theory

The Complete Modern Atom

The History of Atomic Theory

11 Atomic Theory. 2 A HISTORY OF THE STRUCTURE OF THE ATOM.

Atomic Structure History of Atomic Theory. Democritus ( BC) Was the first person to come up with the idea of atom Believed that all matter was.

The Atomic Model Chem 9.

Investigating Atoms and Atomic Theory

History of Atomic Theory

Atomic Theory-Democritus

The Development of the Atomic Theory

Chapter 4: Atomic Structure

 As early as 400 BC, a few people believed that atoms are the building blocks of all matter. Yet, until recently, even scientists had never seen evidence.

Atomic Theory Timeline

The History of Atomic Theory

Atomic Models This model of the atom may look familiar to you. This is the Bohr model. In this model, the nucleus is orbited by electrons, which are in.

Atomic Structure. Way Early Theories Democritus ( BC) –First person to propose that matter is not infinitely divisible –Atomos –Matter is empty.

Investigating Atoms and Atomic Theory Atoms cannot be divided using chemicals. They do consist of parts, which include protons, neutrons, and electrons,

Ch.4 Atomic Structure How do we know atoms exist? Picture, in your mind, what you think an atom looks like.

Atomos: Not to Be Cut or “indivisible” The History of Atomic Theory.

HISTORY OF THE ATOM. Aristotle 400 BC 400 BC - Claimed that there was no smallest part of matter - Claimed that there was no smallest part of matter -

The Changing Models of the Atom

Early Atomic Models Democritus –World is made of two things: empty space and indivisible particles, called atoms –There are different atoms for every material.

Atomic Model History.

Investigating Atoms and Atomic Theory Describe the particle theory of matter. Describe the particle theory of matter. Use the Bohr model to differentiate.

History of Atom Flip Book

History of the Atom Democritus Democritus: It was 400 BC when he came up with the idea that matter could not be divided indefinitely. This lead to the.

Chapter 4 Atomic Structure

Development of the Atomic Theory. Democritus 460 BC - Greek philosopher proposes the existence of the atom ; calls it Atomos meaning indivisible. His.

Development of Atomic Theory Ancient Times | Dalton's Postulates | Thomson's Discovery of Electron Properties | Rutherford's Nuclear Atom | Bohr's Nuclear.

Democritus Dalton (JJ Thompson) Rutherford Bohr Electron Cloud

Atomos: Not to Be Cut The History of Atomic Theory.

2.1 Atoms and Their Structure

Atoms and Their Structure Early Greek Theories 400 B.C. - Democritus crushed substances in400 B.C. - Democritus crushed substances in his mortar and.

The Atom Unit 3, Presentation 1. History of the atom Not the history of atom, but the idea of the atom – The atom was not “discovered” until recently.

MODERN CHEMISTRY CH 3 Atoms: The Building Blocks of Matter.

The History of the Atom.

The Changing Model of the Atom

Atomos The History of Atomic Theory. Atomic Models A model uses ideas to explain facts A model can be changed as new information is collected.

Brief History of Atomic Theory. 1 st atomic models In 400 BC, the model looked like a solid indivisible ball In 400 BC, the model looked like a solid.

1.3 Atomic Theory  Greek philosophers believed that matter was made of atomos that were the smallest pieces of matter.  Aristotle believed matter was.

The History of the Atom. Aristotle  Aristotle was the first scientist that we have record of questioning what stuff was made of.  What did he think?

Chemistry Chapter 4 Notes #1 09/10/10. Democritus Matter is composed of empty space where atoms move Atoms are solid, homogenous, indivisible, and indestructible.

Atomos: Not to Be Cut The History of Atomic Theory.

The Beginning of the Atomic Theory Democritus was a Greek philosopher who was among the first to suggest the existence of atoms. 460 BC – 370 BC.

Atomos: Not to Be Cut The History of Atomic Theory.

Who are these men?.

ATOMIC THEORY Atomic Theory Pioneers Democritus: A Greek philosopher around the year 400 BC. concluded that matter could not be divided into smaller.

ATOMIC THEORY CHAPTER 11.1 IN HOLT TEXTBOOK BCE Ancient Greek Philosopher Matter divided into a smaller and smaller piece the uncuttable piece.

Can you match the scientists’ names to their pictures? Democritus Dalton JJ Thomson Rutherford Bohr De Broglie Schrodinger.

The Changing Model of the Atom From Democritus to Bohr.

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.

Unit 3: Atomic Structure. Atomic Structure  element  matter that is composed of one type of atom  atom  the smallest particle of an element that still.

AIM: Models of the Atom DO NOW: Element Y has two isotopes: Y-27 and Y-29. Y-27 has an abundance of 43% and Y-29 has an abundance of 57%. What is the average.

Unit 3 Development of the Modern Atomic theory Democritus & Dalton Schrodinger Rutherford Thomson Bohr.

Atomic Structure Ch. 4.

Atomic Theory A Brief History.

Presentation transcript:

Atomic Theories Chapter 4.1 How do we know about atoms when no one has ever seen inside an atom?

Greek Philosopher - Democritus Believed it is IMPOSSIBLE to divide matter ad infinitum. Theory: “Atomos” – smallest particle of matter. Lived BCE

Greek Philosopher: Aristotle Theory: All matter consists of 4 elements. – Air – Water – Fire – Earth Theory: Matter can be divided indefinitely. Lived BCE

John Dalton Math & Chemistry teacher Member of the Royal Society Received many awards and honors. Theory (1803): All matter is composed of tiny, solid, indestructible particles – called atoms. – Atoms of same elements are alike in size and mass. – Atoms of different elements have different sizes and masses. – Nickname: “Billiard Ball Theory” Lived (Two thousand years after the Greek philosophers.) Country: England

John Dalton (continued) Example: Electrolysis of water – electro – refers to electricity – lysis – means “to cut” Experiments: He measured amounts of elements and masses of compounds.

John Dalton (continued) This experiment shows: 2 times the VOLUME of hydrogen gas compared to the volume of oxygen. So, there must be twice the proportion of hydrogen atoms as oxygen in each water molecule. Therefore the formula for water is H 2 O.

John Dalton (continued) Also, when he measured the MASS of hydrogen and oxygen, he found out that the ratio of oxygen to hydrogen 8 :1 in every experiment. (Don’t forget there are 2 hydrogen and 1 oxygen atom in every water molecule) Oxygen has a molar mass of 16 g/mole Hydrogen has a molar mass of 1 g/mole

John Dalton Theory: Law of Definite and Multiple Proportions 1. Chemical compounds are formed by the union of 2 or more atoms of different elements. 2. Atoms combine to form compounds in simple, whole number ratios. Examples: CO – carbon monoxide is made of 1 carbon and 1 oxygen atoms CO 2 – carbon dioxide is made of 1 carbon and 2 oxygen atoms H 2 O – water is made of 2 hydrogen and 1 oxygen atoms H 2 O 2 – hydrogen peroxide made of 2 hydrogen and 2 oxygen atoms

JJ Thomson Won numerous awards and prizes for his work. Member of the Royal Society. Experimented with gases and electricity in sealed glass tubes (called cathode ray tubes) showing a glowing stream of particles. Lived Country: England

JJ Thomson Noticed that when he held a magnet up to the tube, the gas was deflected. A positive magnet attracted the stream of particles. A negative magnet repelled the stream of particles. He discovered electrons!

JJ Thomson Thomson’s Theory (1897): Atoms consist of negatively charged particles (we now call electrons) embedded in positive matter. Nicknames: “raisin bun theory” or “plum pudding theory” – electrons are like the raisins or plums in the bread or pudding.

Ernest Rutherford He had many honors, including being President of the Royal Society. Won many awards, including becoming an English knight and baron. Famous Experiment (1911): Gold Foil Experiment Lived Country: England and New Zealand

Rutherford’s Famous Gold Foil Experiment Theories about Atoms: 1. Atoms have a small, dense core (we now call the nucleus) 2. The nucleus is positively charged. 3. The nucleus contains most of the mass of an atom. 4. An atom’s volume is mostly empty space! Rutherford discovered the NUCLEUS of the atom!

Niels Bohr Studied under both JJ Thomson and Ernest Rutherford. President of the Royal Danish Academy of Sciences Foreign member of the Royal Society. Won Nobel Prize in Physics in Worked with leading scientists on the Atomic Energy Project. Lived Country: Denmark; worked in England and USA

Niels Bohr Experiment: Bohr studied the bright-line spectra of hydrogen. He measured the energy released by hydrogen’s energized electrons when they return to ground state. He noticed that the released energy was in certain packets of light energy (called photons).

Niels Bohr Theory (1913): Electrons travel in particular orbits around the atom’s nucleus like planets around the sun. Also, the chemical properties of each element is determined by the number of electrons in the outer orbit of its atoms.

Modern Theory of the Atom De Broglie & Shrodinger’s work led to the develop of the most current model of the atom called the Electron Cloud Model There is a nucleus containing positively charged protons and neutrons which have no charge There is a space surrounding the nucleus called the “Electron Cloud” which is a probable location of where the electrons are found.