Chapter Overview The Structure of the Atom Chapter 4..\..\Movies\Atoms.MOV 4.1 - Early Theories of the Atom 4.2 - Subatomic Particles 4.3 - How Atoms.

Slides:



Advertisements
Similar presentations
The Structure of the Atom
Advertisements

Development of the Atomic Theory
Atomic Mass and the Mole. Relative Atomic Mass Units of grams are TOO LARGE for atoms! Relative atomic mass – compare to small particles – amu – “atomic.
Chapter 2 Atoms, molecules, and ions
Chapter 3 History of the Atom.
“Atomic Structure” Essential Question: Describe how the model of the atom has changed since the Greek idea of “Atomos”
Drill: Calculate the mass in kg of material with a density of 7.50 g/mL in a 2.0 m x mm 4.00 x 10 5  m container. 1 cm 3 = 1 mL.
Chemistry Sheds Light on Our Lives Unit 4 Atoms and Light
CHAPTER 4 – THE ATOM John Dalton’s Atomic Theory (19 th Century) 1) All matter is composed of small particles called atoms 2) All atoms of an element.
Chapter 4 Structure of the Atom. History In the 1800’s, early philosophers believed all matter consisted of either air, earth, water, or fire. In the.
Atomic Structure.
Chapter 4 Atomic Theory.
Atomic Structure Chapter 4
Atoms and Their Structure Chapter 4. Atoms Elements are made of particles called atoms Atoms are the smallest pieces of matter that contain all the properties.
Chemistry Chapter 3 Atoms: The Building Blocks of Matter.
Lecture Notes Chapter 4-The Structure of the Atom
Chapters 4, 5.1, + 25 HISTORY OF THE ATOMIC MODEL.
Atomic Structure Atoms and their structure Mr. Bruder.
Chapter 2 Notes Atomic Structure. Atoms Democritus – Ancient Greek Science dude, 1 st proposed the idea of atoms, tiny indivisible particles Atomos –
Atomic Theories. Atomic timeline Your poster should contain: –The date the theory was developed –A picture of the ‘model’ –The name of the main contributor.
The Structure of the Atom Chemistry 1. 2 Learning Objectives for this Chapter: 1.Describe changes in the atomic model over time and why those changes.
The Structure of the Atom
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Table of Contents Chapter 3 Atoms: The Building Blocks of Matter.
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.
Atoms: Development of the Atomic Theory 1. Ancient Belief Ancient Greeks believed that all things were made up of earth, wind, fire, and water. Ancient.
Atomic Structure. 1. Democritus: Around 300 BC, a Greek philosopher, Democritus stated that everything is made up of tiny, invisible particles He said.
Chapter 3 Atoms: The Building Blocks of Matter. Objectives: Students should be able to: Summarize the essential points of Dalton’s atomic theory. Describe.
PreAP Chemistry Chapter 3 Chapter 3 Outlines Due to the box NOW Not later today!
Chapter 5 – Atomic Structure Atoms Structure of An Atom Distinguish Between Atoms The Periodic Table.
Atoms: The Building Blocks of Matter. Dalton’s Atomic Theory (1803) 1.All matter is made of atoms. 2.Atoms of the same element are identical. Atoms of.
Foundations of Atomic Theory The transformation of a substance or substances into one or more new substances is known as a chemical reaction.
The Atom Chapter 3. From Idea to Theory Democritus, Greek philosopher, 400 B.C., introduced the concept of an atom, an ‘indivisible’ particle. Democritus,
Chapter 3 History of the Atom.
Chapter 4 The structure of the atom. Atom Smallest part of an element that retains the properties of the element.
The Structure of the Atom Chapter 3 Chemistry: Matter and Change.
Unit 2 - Lecture 1: Structure of the Atom
Unit 4: Atomic Theory Structure of the Atom (& Radioactivity)
Chapter 3 – Atoms: The Building Blocks of Matter 3.1: Atomic Theory History A. 1700s: quantitative studies of chemical reactions led to several laws: 1.
The Structure of the Atom Chapter Early Theories of the Atom Subatomic Particles How Atoms Differ Unstable Nuclei & Radioactivity.
Atomic Structure Chapter 4. Dalton’s Atomic Theory 4.1 John Dalton – 18 th century All matter is composed of atoms All atoms of a given element are identical.
MODERN CHEMISTRY CH 3 Atoms: The Building Blocks of Matter.
PreAP Chemistry Chapter 4 Chapter 4 Annotation Questions Due to the box NOW! Late is only worth 60%, but is better than 0%!
The Atom Chapters 4-5 Atomic Theories Democritus ~ 400 BC believed that atoms were indivisible and indestructible Dalton ~ 1800’s Developed through experiments.
Chapter 4 Structure of the Atom. Section 4.1 Democritus ( BC) –Matter is composed of empty space through which atoms move –Atoms are solid, homogeneous,
Rev 6/7/ BC Atomic Model Development.
The Structure of the Atom
Greek Philosop hers Dalton’ s Atomic Theory How atoms differ Radioac tivity Types of radiatio n The atom Subatomic.
Smallest particle of an element that retains the properties of the element.
Chemistry Chapter Three – Atoms: The Building Blocks of Matter South Lake High School Science Department Ms. Sanders.
Ch. 3 - Atomic Structure Subatomic Particles – show powers of ten ect…..
History of the Atom. Atoms and Elements Any material that is composed of only one type of atom is called an element. An atom is the smallest particle.
The Structure of the Atom Chemistry – Chapter 4. Early Theories of Matter Philosophers ◦ Democritus was first to propose Atomic Theory:  Matter composed.
Atomic Theory & Periodic Table Unit 3 Part 1 (Ch. 4 & 5) Atomic Theory Introduction, Isotopes.
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.
1 UNIT 2 Atoms, Molecules, and Ions. 2 The Power of 10 nceopticsu/powersof10/
Ch. 3 - Atomic Structure Subatomic Particles.
Chapter 3: Discovering the Atom and Subatomic Particles
T HE S TRUCTURE O F T HE A TOM Models and Theories Subatomic Particles Atomic Number and Mass Unstable Nuclei.
1 The History of Atomic Theory A long and winding road Section 4.1.
UNIT 2 Atoms, Molecules, and Ions. 1. Each element is composed of extremely small particles called atoms. 2. All atoms of a given element are identical.
Atoms: The Building Blocks of Matter
Unit 2 - Lecture 1: Structure of the Atom
The Structure of the Atom
SECTION III: A WORLD OF PARTICLES
4-1 Early Ideas of the Atom
Atomic Structure and Timeline
The Building Blocks of Matter
Atomic Structure An atom is the smallest particle of an element that retains its identity in a chemical reaction. Although early philosophers and scientists.
4.1 Defining the Atom 4.2 Atomic Structure
Presentation transcript:

Chapter Overview

The Structure of the Atom Chapter 4..\..\Movies\Atoms.MOV Early Theories of the Atom Subatomic Particles How Atoms Differ Unstable Nuclei & Radioactivity Ann Dau – CHEMISTRY 112

4.1 Early Theories of Matter Dalton’s Atomic Theory 1.All matter is composed of extremely small particles called atoms. 2.All atoms of a given element are identical. Atoms of different elements are different from one another. 3.Atoms cannot be created or divided into smaller particles or destroyed. 4.Different atoms combine in simple whole number ratios to form compounds. 5.In a chemical reaction, atoms are separated, combined, or rearranged. Dalton’s Atomic Model Atom - the smallest particle of an element that retains the properties of the element.

4.1 Early Theories of Matter E. Goldstein discovered the proton in J.J. Thomson discovered the electron in 1897 during cathode ray tube experiments in the late 1890’s.

4.1 Early Theories of Matter Robert A. Millikan determined the mass and charge of the electron in –one unit of negative charge –mass is 1/1840 of a hydrogen atom

4.1 Early Theories of Matter In 1911 Ernest Rutherford discovered the nucleus during his gold foil experiment.

4.1 Early Theories of Matter Ernest Rutherford’s gold foil experiment.

4.1 Early Theories of Matter Neils Bohr developed the planetary model of the atom –Electrons are in a particular path have a fixed energy –Energy level-region around a nucleus where the electron is likely to be moving

4.1 Early Theories of Matter Erwin Schrodinger developed the Quantum Mechanical Model –Describes the electronic structure of the atom as the probability of finding electrons within certain regions of space

4.1 Early Theories of Matter James Chadwick discovered the neutron in In 1913 Henry Mosley used X-rays to count the number of protons in the atomic nuclei of different atoms.

The Atomic Theory All elemental substances are made up of tiny indivisible particles called atoms. Atoms of different elements have different properties. In an ordinary chemical reaction, atoms of elements maintain their identities. Compounds are made when atoms of different elements combine...\..\Movies\atom model.MOV

Parts of the Atom Protons give atoms their identity!

Atomic Structure Nucleus Protons and neutrons Both about the same mass (Table 2.1 Text) About cm radius for gold atom Most of atomic mass found in nucleus Outer periphery electrons Less massive Electronic structure covered later..\..\Movies\atomic model.MOV

4.2 Subatomic Particles & the Nuclear Atom Located within the Nucleus –Proton (p + ) Positively charged particle (each carries a charge of +1) Relative mass = 1 amu Actual mass = X kg –Neutron (n 0 ) Neutrally charged particle Relative mass = 1 amu Actual mass = X kg Serves as the glue that holds the nucleus together as well as a buffer between the charges of protons and electrons

Subatomic Particles Located outside the nucleus in the electron cloud –Electron Negatively charged particle (each carries a charge of -1) Relative mass = 1/1840 amu Actual mass = 9.11 X kg The electron is the part of the atom that will function in bonding and reactions

4.3 How Atoms Differ Atomic Number –the number of protons in the nucleus of an atom –indicated at the top of the element’s block on the periodic table 8O Mg Oxygen has an atomic number of 8 There are 8 protons in an atom of Oxygen Magnesium has an atomic number of 12 There are 12 protons in an atom of Magnesium

Isotopes Atoms of the same element with the same number of protons, but different numbers of neutrons Since the atoms have different numbers of neutrons, they also have different mass numbers –Mass number = # of protons + # of neutrons

Abbreviating Isotopes Hyphen Notation –Simply write the Name of the atom, put a hyphen, and then write the mass number Carbon-12 vs. Carbon-14 –Carbon 12 has 6 protons and 6 neutrons –Carbon 14 has 6 protons and 8 neutrons Nuclear Designation –Element symbol is written in the center –Mass number goes in the upper left corner –Atomic number goes in the lower left corner C 12 6

Different Isotopes Identify the number of protons, neutrons, and electrons each of the following have. Boron-10 Boron Cl 66 Zn Br p + : ________ n o : ________ e - : ________ p + : ________ n o : ________ e - : ________ p + : ________ n o : ________ e - : ________

Sample Problem 2.2Determining the Number of Subatomic Particles in the Isotopes of an Element PROBLEM: Silicon(Si) is essential to the computer industry as a major component of semiconductor chips. It has three naturally occurring isotopes: 28 Si, 29 Si, and 30 Si. Determine the number of protons, neutrons, and electrons in each silicon isotope.

Calculating Atomic Mass Mass Number –the number of protons + neutrons in a given isotope Atomic Mass –The weighted average mass of all of the isotopes of that element [(Mass of isotope A)(percent abundance )] + [(Mass of isotope B)(percent abundance)]

Practice Calculating Atomic Mass Calculate the atomic mass of helium given the following information: There are two naturally occurring isotopes of helium: Isotope% AbundanceMass helium helium

Practice Calculating Atomic Mass There are two naturally occurring isotopes of helium: Isotope % Abundance Mass helium helium ( x ) + ( x ) = =

Practice Calculating Atomic Mass There are three naturally existing isotopes of silicon: silicon-28, silicon-29, and silicon-30. Their percents of natural abundance is listed respectfully: %, 4.70 %, and 3.09 %. Calculate the average atomic mass of silicon and express your answer in 4 significant digits.

Sample Problem 2.3 Calculating the Atomic Mass of an Element Silver (Ag: Z = 47) has 46 known isotopes, but only 2 occur naturally, 107 Ag and 109 Ag. Given the following data, calculate the atomic mass of Ag: IsotopeMass(amu)Abundance(%) 107 Ag 109 Ag

Atoms, Ions, and Isotopes Ions and isotopes are atoms…they are specific types of atoms. Ions: atoms that have a charge; either positive or negative What would allow an atom to be an ion? Isotopes: a relationship between two atoms in which they have the same number of protons and different numbers of neutrons. Are isotopes technically atoms of the same element?

Ions Atoms that have gained electrons to become ___________________ charged. Atoms that have lost electrons to become ___________________ charged. Key: Has the identity of the atoms changed? Why?

4.4 Unstable Nuclei & Radioactive Decay Nuclear Reactions –reactions that involve a change in the nucleus of an atom. Radioactivity –the spontaneous release of radiation. Radiation –rays and particles emitted by radioactive materials Radioactive atoms emit radiation because their nuclei are unstable. There are three main types of radiation –Alpha decay –Beta decay –Gamma decay

Alpha ( α ) radiation two protons and 2 neutrons Positive charge Symbols:  4  4 He 2 2 reduces the atomic number by 2 reduces the mass by 4

Beta ( β ) radiation Fast moving electron Negative charge Symbols:  0  increases the atomic number by 1 does not change the mass

Gamma ( γ ) radiation high energy radiation released with alpha and beta radiation symbol:  0  0 does not change the mass or atomic number

Half lives The time it takes for 1/2 of the mass of the isotope to be decayed. If I have a 60g sample and the half life is 2 years, how long will it take for there to be 7.5g left of the sample? 60g  30g  15g  7.5g 2 years 4 years 6 years So, it takes 6 years for the 60g sample to decay into 7.5g.