Atomic Theory.

Slides:



Advertisements
Similar presentations
Atomic Theory.
Advertisements

History of the Atom.
The Building Blocks of Matter
From Philosophical Idea to Scientific Theory
Atomic Theories.
ATOMIC STRUCTURE AND HISTORY
Atomic Structure. What is an Atom? The smallest part of an element.
Atomic Theory “History of. . . ”.
 You cannot see them, yet they make up everything…
Atomic Theory and the Atom
History of Atomic Theory
History of Atomic Theory 1
AIM: Models of the Atom DO NOW:
Chapter 2 Atoms, molecules, and ions
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.
Chapter 3 Atoms and Atomic Structure Write the bullets that are in black font.
Atomic Discovery Early Models of the Atom 400 B.C. – Democritus proposed the existence of fundamental particles of matter that were indivisible and indestructible.
History of Atomic Structure
PART ONE ATOMIC THEORY. Over the course of thousands of years our idea of what matter is made of and what the atom looks like has changed dramatically.
Atomic Theory Chapter 3 Sections 1 &2 9/18/14.
The Development of the Atomic Theory
SCH4C UNIT 1: Matter and qualitative Analysis Atomic Theory
Exam 3 – Unit 2 Complete individually. No notes. No talking.
Atoms and Moles.  All matter is made of atoms  Law of definite proportions  Water is 88.8 % oxygen and 11.2 % hydrogen  Law of conservation of mass.
, who was from was the first person to use the term atom during B.C.  Democritus defined the atom as being.  opposed Democritus because believed that.
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.
Developing a Model of the Atom The History of Atomic Theory.
A History of Atomic Theory & Basic Atomic Structure Chapter 3: The Atom Big Idea: Physical, chemical and nuclear changes are explained using the location.
Atomic Theory “History of... ”. The Ancient Greeks Democritus and other Ancient Greeks were the first to describe the atom around 400 B.C. The atom was.
The Atom Chapter 4.
Ch.4 Atomic Structure How do we know atoms exist? Picture, in your mind, what you think an atom looks like.
Development of Atomic Structure How long have people been interested in understanding matter and its structure? A.Thousands of years B.Hundreds of years.
The Story of the Atom History and Other Early Stories.
Atoms, Molecules and Ions
Chapter 4: Atomic Structure Democritus believed that matter was made up of particles. he called nature’s basic particle an “atom”. The …… Aristotle’s idea.
Atomic Theory 15,000 kilotons.  Dismissed idea of the atom. Early Greeks Two schools of thought:  Matter is made of indestructible particles called.
Atoms: The Building Blocks of Matter. PART 1  Democritus [400 B.C]  Greek philosopher  Hypothesized: Nature has a basic indivisible particle of which.
A Brief History of Chemistry
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.
The Atomic Theory of Matter By Shaffer Lisle. The First Theories John Dalton’s proposed theories: Each element is composed of particles called atoms.
EARLY MODELS OF THE ATOM Models of Matter A model is a tentative description of a system or theory that accounts for all of its known properties Models.
Foundations of Atomic Theory The transformation of a substance or substances into one or more new substances is known as a chemical reaction.
EARLY ATOMIC THEORY CHAPTER 3. THE ATOM: FROM PHILOSOPHY TO SCIENTIFIC THEORY 400 BC – Democritus came up with the idea of the ________ Nature’s basic.
Atoms and Their Structure Early Greek Theories 400 B.C. - Democritus crushed substances in400 B.C. - Democritus crushed substances in his mortar and.
Development of the atomic theory. Important laws Law of conservation of mass – Mass is neither created or destroyed during ordinary chemical reactions.
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.
The Atom. Dalton’s Atomic Theory 1.Elements are made of tiny particles called atoms. 2.All atoms of a given element are identical. 3.The atoms of a given.
ATOMS: The Building Blocks of Matter Objectives 1.Law of conservation of mass 2.Law of definite proportions 3.Law of multiple proportions 4.Dalton’s Atomic.
Chapter 3 Atoms and matter. laws The transformation of a substance or substances into one or more new substances is known as a chemical reaction. Law.
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 What is chemistry? –Chemistry is the study of matter, what it is made of, and how it changes. What is matter? –Matter is anything that… Has.
Chapter 3 Atoms : The Building Blocks of Matter. Foundations of Atomic Theory  Several basic laws were after the 1790’s (emphasis on quantitative analysis):
Models of the Atom. Ancient Greece 300 BC in Greece School of thought that matter is made up of tiny indivisible, invisible, indestructible, fundamental.
The Atom - Scientists. Philosophers Democritus – believed matter was not infinitely divisible THERE WERE NO EXPERIMENTS TO TEST HIS IDEAS Matter is composed.
Foundations of the Atomic Theory. Don’t forget how we got here, thanks to Democ., Aristotle, and the Particle Theory of Matter.
Chapter 3 Atoms: The Building Blocks of Matter. Lesson 1.1: Early Atomic Theory Learning Target: I will understand the history and structure of the atom.
Atomic Theory In 1808, the English Chemist John Dalton proposed the first theory of the nature of matter in stating that all matter was composed of atoms.
Goal 5.01 Atomic Theory. Basic Laws of Chemistry Law of conservation of massLaw of conservation of mass: mass is neither created or destroyed during chemical.
Chapter 3: Discovering the Atom and Subatomic Particles
Atomic Theory and the Atomic Model. Objectives Describe evidence that Greek philosophers used to develop the idea of atoms. Distinguish between a scientific.
Chpater Review Atomic Theory Atomic structure Valence electrons.
Atomic Theory “History of. . . ”.
Early Models of the Atom
Chapter 3 Brian, Eric, Harry, Rafi.
Honors Coordinated Science II Wheatley-Heckman
Structure of Matter A. Atomic Theory and Atomic Structure
Presentation transcript:

Atomic Theory

How did we know what matter is? Different schools of thought in Ancient Greece: Aristotle had the idea that all matter was continuous and that matter’s characteristics were not independent but changeable Democritus had the idea that matter was made up of tiny indivisible particles that were surrounded by free space

What do we know about a chemical reaction? reactants  products What’s happening to the matter in this process? When a solid (such as wood) is burned, where does the matter of the wood go? A chemical reaction is the transformation of one or more substances into one or more new substances

Law of Conservation of Mass reactants  products What’s happening to the matter in this process? Law of conservation of mass: Mass is neither created nor destroyed during ordinary chemical reactions or physical changes

Law of Definite Proportions Think of doubling a recipe: if one type of cake always needs 1 egg and 2 cups of sugar, two cakes of that variety will need 2 eggs and 4 cups of sugar, but it will be the same type of cake A chemical compound will contain the same elements in exactly the same proportions by mass regardless of the sample size or source of the compound. Think back to our SRQ, sucrose is always sucrose!

Law of Multiple Proportions Think of modifying a recipe: if one type of cake always needs 1 egg and 2 cups of sugar, a different variety might need 2 egg and 2 cups of sugar, we’d say the second cake needs twice as many eggs as the first If two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element (in relation to the mass of the first element) is a whole number

Dalton’s Atomic Theory He wanted to explain the 3 laws of matter that had been observed All matter is composed of extremely small particles called atoms Atoms of a given element are identical in size, mass, and other properties; atoms of different elements differ in size, mass, and other properties

Dalton’s Atomic Theory Atoms cannot be subdivided, created, or destroyed Atoms of different elements combine in simple whole-number ratios to form chemical compounds In chemical reactions, atoms are combined, separated, or rearranged.

Ob-scertainer You can’t see something, but you know it’s there… you feel it moving… How is it moving? Do your best to determine the movement of the “particle” in your containers

Ob-scertainer Solutions #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12

The Structure of the Atom Even though Dalton was a little off, and it was discovered that atoms are divisible: An atom is the smallest particle of an element that retains the chemical properties of that element.

Discovery of the Electron What are some relationships between matter and electricity? (where have you experienced electricity and how has matter been a part of this?)

Discovery of the Electron Scientists used a cathode ray tube Inside was gas and two metal disks at each end of the tube (there was no vacuum or absence of matter) Electricity was passed through the tube They OBSERVED: A thin glowing stream formed between each metal end, starting at the cathode end.

Discovery of the Electron Scientists used a cathode ray tube

Discovery of the Electron Scientists used a cathode ray tube observed: The stream could be manipulated by magnetic fields The stream moved away from a negatively charged object The stream moved toward a positively charged object

Charge and Mass of the Electron Millikan ran an experiment that allowed him to measure the charge of an electron He knew the mass of the droplets, and he knew the charge he was applying, From this, he was able to deduce the charge and mass of an electron Always use what you observe!

Charge and Mass of the Electron Millikan ran an experiment that allowed him to measure the charge of an electron He knew the mass of the droplets, and he knew the charge he was applying, From this, he was able to deduce the charge and mass of an electron

New Model? Thomson proposed a new model for the atom to include the newly discovered electrons: The Plum Pudding Model

Discovery of the Atomic Nucleus Rutherford and his associates: shot alpha particles (positively charged helium ions) at a sheet of gold foil. How do the masses of the alpha particles compare to the masses of gold atoms? Most particles managed to fly right through…

Discovery of the Atomic Nucleus BUT some alpha particles were deflected to a ridiculous degree! Rutherford and his associates were not expecting this! It was as if the particles were dramatically repulsed by something If atoms were like the plum pudding model, how would they be deflected?

Discovery of the Atomic Nucleus Rutherford concluded that the majority of an atom’s mass was densely packed positively charged protons and neutral neutrons located at the center of the atom Where were the electrons??

Discovery of the Atomic Nucleus Bohr proposed a new model to replace the Plum Pudding model. His model proposed that an atom had a tiny nucleus of protons and neutrons and a large orbital of electrons, like how the planets orbited the sun.