Chapter 3: Chemical Foundations, Elements, Atoms, and Ions The atom, Compounds and Average Atomic Mass.

Slides:

Advertisements

Similar presentations

Ch. 5: Atomic Structure Standards: Matter consists of atoms that have internal structures that dictate their chemical and physical behavior. Targets:

Advertisements

Chapter 5: Atomic Theory: The Nuclear Model of the Atom

Chapter Two: Atoms, Molecules and Ions

Christopher G. Hamaker, Illinois State University, Normal IL

Atomic Structure. Subatomic Particles (Particles that make up an atom) ● Proton (p+) - Positively charged - Found in the nucleus - Large mass ●Neutron.

Unit Six: Atomic structure

Chapter 2 Atoms, molecules, and ions

Chapter 3 History of the Atom.

Elements, Atoms, Ions The Elements.

Chapter 4 Atomic Structure

Unit 3 Language of Chemistry Part 1 Zumdahl: Chapter 4 Holt: Chapter 3.

Chapter 4: Elements, Atoms, and Ions Chemistry 1020: Interpretive chemistry Andy Aspaas, Instructor.

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.

Understand the experimental design and conclusions used in the

Chapter 3 Atoms and Elements

Chapter 3Atoms and Elements 3.1 Elements and Symbols Elements are pure substances that cannot be separated into simpler substances by ordinary laboratory.

Chapter 4: Atomic Structure

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 History, Structure, Properties and Forces Chapter 4.

Elements, Atoms, and Ions. Elements 88 occur naturally Table most abundant elements in Earth’s crust, oceans, and atmosphere Table Abundance.

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

Section 3.3 Atomic Structure

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.

Chapter 3 Atoms and Elements 3.4 The Atom 1. The Law of Multiple Proportions and Dalton’s Atomic Theory Elements are made up of tiny particles called.

ATOMIC THEORY. Defining the Atom  An atom is the smallest particle of an element that retains its identity in a reaction.  The basic building blocks.

Chapter 4. Greek philosopher (460 B.C.-370 B.C.) 1 st to suggest the existence of atoms Said that atoms were indivisible and indestructible Democritus’s.

Slide 1 Section 3.2 Atoms & Compounds Objectives  To learn about Dalton’s Theory of atoms  To understand and illustrate the Law of constant composition.

ATOMIC STRUCTURE Modern theory of matter. LET’S REVIEW Dalton’s atomic theory – Elements are made of atoms ; all atoms of an element are identical, atoms.

Foundations of Atomic Theory The transformation of a substance or substances into one or more new substances is known as a chemical reaction.

Chapter 3 History of the Atom.

Atoms. Elements vs. Compounds  Elements can NOT be chemically broken down to a simpler substance, compounds can. (Ex. H 2 O  H 2 + O 2 )  Pure substances.

The Structure of the Atom Chapter 3 Chemistry: Matter and Change.

Atomic Theory and Structure. The Theory of the Atom _________ __, a Greek teacher in the 4th Century B.C., first suggested the idea of the atom. _________.

Atoms, Molecules and Ions Chapter 2. Foundations of Atomic Theory Law of conservation of mass: Antoine Lavoisier –Mass is neither created nor destroyed.

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.

Ch. 5: Atomic Structure Standards: Matter consists of atoms that have internal structures that dictate their chemical and physical behavior. Targets: State.

Ariana Garcia-Minsal. Dalton's Atomic Theory - (1808) His atomic theory could be summarized as: 1)Matter is composed of tiny and indivisible particles.

1 The Structure of the Atom. 2 Early Theories of Matter.

Ch. 3 Atoms: The Building Blocks of Matter. Table of Contents Chapter 3 Atoms: The Building Blocks of Matter Section 1 The Atom: From Philosophical Idea.

Atoms CHAPTER 4. Democritus develops the idea of atoms 460 B.C. he pounded up materials until he had reduced them to smaller and smaller particles which.

Smallest particle of an element that retains the properties of the element.

Atomic Structure CHAPTER 4. Defining the Atom ✴ An atom is the smallest particle of an element that still has the chemical properties of that element.

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.

1 Isotopes & Ions. What’s in an atom of a given element? An atom has three subatomic particles: Proton = positive (+) charge Neutron = no charge Electron.

Unit 3 Atomic Theory. Important terms to know Atoms – The fundamental unit of which elements are composed. Element – A substance that cannot be decomposed.

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.

C H E M I S T R Y Chapter 2 Atoms, Molecules, and Ions.

1 UNIT 2 Atoms, Molecules, and Ions. 2 The Power of 10 nceopticsu/powersof10/

Unit 3 Atomic Structure and Periodicity. Dalton’s Atomic Theory 1.All matter is composed of _____________. 2. Atoms of the same element are _______________.

1 The Atom Atomic Number and Mass Number Isotopes.

Chapter 3 Atoms and their structure History of the atom n Democritus, a Greek philosopher, originally came up with the idea of an atom (around 400 BC)

Chapter 3: Discovering the Atom and Subatomic Particles

Do Now: Match the scientist with their contribution to the atom A. Dalton1. Mass of electron B. Thomson2. atomic theory C. Milikan3. discovered electron.

Atomic Structure.

Introduction to Atomic Theory. History of the atom Democritus (400 BC) suggested that the material world was made up of tiny, indivisible particles atomos,

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.

Atomic Structure. Early Theories of Matter Democritus ( BCE) Democritus ( BCE) Greek philosopher Greek philosopher First to propose the.

Atoms: The Building Blocks of Matter Chapter 3 Pages

Atomic Structure Unit 3. What is an Atom? 

Chapter 4: Atomic Structure Distinguishing Among Atoms.

Chapter 4 Atomic Structure. Defining the Atom  All elements are composed of particles called atoms  All atoms of the same element are identical  Atoms.

Atomic Structure. Defining the Atom  All elements are composed of particles called atoms  All atoms of the same element are identical  Atoms of different.

Atomic Structure.

Atoms: The Building Blocks of Matter

THE STRUCTURE OF THE ATOM

Chapter 3 History of the Atom.

Chapter 3 Chemical Foundations: Elements, Atoms, and Ions

Chapter 4 Atomic Structure.

Presentation transcript:

Chapter 3: Chemical Foundations, Elements, Atoms, and Ions The atom, Compounds and Average Atomic Mass

Learning Targets You will learn about Dalton’s theory of atoms. You will learn about important features and experiments discovering the atomic structure. You will learn how chemical formulas represent compounds. You will learn how to calculate the average atomic mass of an element.

Dalton’s Atomic Theory Most natural materials are mixtures of pure substances (either elements or compounds) Given compound always contains same proportions (by mass) of elements - “Law of constant composition”. Explanation of these observations known as Dalton’s atomic theory.

Dalton’s Atomic Th. Cont. 1. Elements are made of tiny particles called atoms 2. All atoms of a given element are identical 3. Atoms of one element differ from atoms of another element

Dalton’s Atomic Th. Cont. 4. Atoms of one element can combine with atoms of other elements to form compounds. A given compound always has the same relative numbers and types of atoms 5. Atoms are indivisible in chemical processes. CANNOT be created or destroyed in reactions, only grouped together differently

Formulas of Compounds A chemical formula represents the types of atoms and the number of each type of atom in a compound. (H 2 O, CaCl 2, NaNO 3 ) When a compound is formed between ions, the compound must be neutral in charge. This affects the numbers of each type of atom.

Rules for Writing Formulas 1. Each atom present is represented by its element symbol. 2. The number of each type of atom is indicated by a subscript written to the right of the element symbol. 3. When only one atom of a given type is present, the subscript 1 is not written.

Formulas of Compounds-Practice Write the formula for each of the following compounds, listing the elements in the order given: –Each molecule of a compound that has been implicated in the formation of acid rain contains one atom of sulfur and three atoms of oxygen. Each molecule of a certain compound contains two atoms of a nitrogen and five atoms of oxygen.Answers: SO 3 N2O5N2O5N2O5N2O5

Formulas of Compounds-Practice The pairs of ions contained in several ionic compounds are listed below. Give the formula for each compound: –Ca 2+ and Cl - –Na + and S 2- –Ca 2+ and P 3- Answers: CaCl 2 Na 2 S Ca 3 P 2

Formulas of Compounds-Try on own Write the formula for each of the following compounds, listing the elements in the order given. –A molecule contains four phosphorus atoms and ten oxygen atoms. –A molecule contains one uranium atom and six fluorine atoms. – A molecule contains one aluminum atom and three chlorine atoms.Answers: P 4 O 10 UF 6 AlCl 3

Formulas of Compounds-Try on own Use the pairs of ions below to give the formula for the compound containing these ions. –Ba 2+ and O 2- –Al 3+ and S 2- –K + and P 3- Answers:BaO Al 2 S 3 K3PK3PK3PK3P

The atom Electron: negatively charged subatomic particle Nucleus: dense, positively charged center of atom Neutron: subatomic particle with zero charge If talking about atom IT IS NEUTRAL! If talking about ions, compounds are being formed.

Scientist #1 – J.J. Thomson –Atoms must contain negative particles called electrons (repelled by negative part of electric field) –Atoms must contain positive particles to balance the atom to make the atom a zero overall charge

Scientist #2 – William Thomson –The Plum Pudding Model –Uniform positive charge with negative electrons scattered through to neutralize charge. –Think of a batch of chocolate chip cookies - batter similar to the pudding (uniform positive charge) –Chocolate chips like raisins in pudding - negative electrons scattered through to neutralize the charge

Scientist #3 – Ernest Rutherford –Changed previous ideas about the atom dramatically –Alpha particles –Some of these particles were deflected during their flight through air. This deflection proved there was a center of positive charge (the nucleus) and it must contain protons –Protons and neutrons believed to be same weight, electrons MUCH smaller

Calculating average atomic mass Isotopes exist in different abundances. For example, an element may have 3 isotopes but one exists over 90%, another less than one % and another less than 10% To continue with that example, each isotope has a respective mass with each percent it represents.

Calculating average atomic mass So how do we calculate an average atomic mass to put on the periodic table? A problem like this would look like the following: –An element consists of 90.51% of an isotope with a mass of amu, 0.27% of an isotope with a mass of amu and 9.22% of an isotope with a mass of amu. Calculate the average atomic mass and identify the element.

Calculating average atomic mass How do you solve this problem to get an average mass? –1. You change your percents to decimals. –2. You multiply the decimal number and its respective mass for each pair of numbers they give. –3. You add those multiplied numbers together, round off 3-4 places to be safe and match up the mass you calculated to an element.

Calculating average atomic mass So let’s look at the problem from earlier: –An element consists of 90.51% of an isotope with a mass of amu, 0.27% of an isotope with a mass of amu and 9.22% of an isotope with a mass of amu. Calculate the average atomic mass and identify the element.

Calculating average atomic mass 1. You change percents to decimal form 90.51%  %  %  You multiply the decimal number and its respective mass for each pair of numbers they give % .9051 x amu 0.27% .0027 x amu 9.22% .0922 x amu

Calculating average atomic mass 3. You add those multiplied numbers together, round off 3-4 places to be safe and match up the mass you calculated to an element. (.9051 x amu = ) +(.0027 x amu = ) +(.0922 x amu = ) ELEMENT?

Calculating average atomic mass It should be Neon (Ne)

Try on your own The element magnesium has three stable isotopes with the following masses and abundances: IsotopesMass (amu)Abundance Mg % Mg % Mg % Calculate the average atomic mass of Mg.

Answer Can compare with mass on periodic table to make sure correct.

Recap What are the components of Dalton’s law of atomic theory? Who contributed to the thoughts about atom structure? What is an atom comprised of? What does a chemical formula represent? How do you calculate the average atomic mass of an element?