Chapter 4 - cpChapter 4 - cp

AtomsAtoms

4.1 Journal – Using Analogies4.1 Journal – Using Analogies“If I have the belief that I can do it, I shall acquire the capacity to do it even if I may not have it “If I have the belief that I can do it, I shall acquire the capacity to do it even if I may not have it

at the beginning.at the beginning. -Mahatma Gandhi-Mahatma Gandhi

The network of blood vessels in your body is like the The network of blood vessels in your body is like the network of streets and highways in a large city. How network of streets and highways in a large city. How are the two networks similar? Both networks are used are the two networks similar? Both networks are used to transport objects from one location to another. The to transport objects from one location to another. The comparison is an example of an analogy. An analogy comparison is an example of an analogy. An analogy uses a similarity to compare two objects or systems. uses a similarity to compare two objects or systems. A familiar object is often used to help explain a less A familiar object is often used to help explain a less familiar object. familiar object.

1.1. Atoms in compounds are like bricks in a wall. Explain Atoms in compounds are like bricks in a wall. Explain this analogy. this analogy.

2.2. Think of and explain another analogy for atoms in Think of and explain another analogy for atoms in compounds. compounds.

3.3. WORK ON THE “ATOMIC MATH” WORKSHEET – use WORK ON THE “ATOMIC MATH” WORKSHEET – use section 4.2 vocabulary to help you with the top section 4.2 vocabulary to help you with the top sectionsection

4.2 Journal4.2 Journal“If I have the belief that I can do it, I shall acquire the capacity to do it even if I may not have it “If I have the belief that I can do it, I shall acquire the capacity to do it even if I may not have it

at the beginning.at the beginning. -Mahatma Gandhi-Mahatma Gandhi

Take out your homework.Take out your homework.

Begin filling out the boxes on the Begin filling out the boxes on the Periodic Table Basics sheets.Periodic Table Basics sheets.

Studying AtomsStudying Atoms

ANCIENT GREEKS-ANCIENT GREEKS-DEMOCRITUS:DEMOCRITUS:

““atomos” = indivisible, uncutatomos” = indivisible, uncut Different types of atoms with specific Different types of atoms with specific

propertiesproperties

ARISTOTLE:ARISTOTLE: Only 4 elements Only 4 elements No limit to divisionsNo limit to divisions

Studying AtomsStudying AtomsDALTON’S ATOMIC THEORY:DALTON’S ATOMIC THEORY: all matter is all matter is made of particles that cannot be dividedmade of particles that cannot be divided

Evidence:Evidence: Compounds have fixed compositionsCompounds have fixed compositions

HH22OO

2g H always combines with 8g O2g H always combines with 8g O

4g H always combines with 16g O4g H always combines with 16g O

4.1 Studying Atoms4.1 Studying AtomsDALTON’S ATOMIC THEORY:DALTON’S ATOMIC THEORY: all matter is all matter is made of particles that cannot be dividedmade of particles that cannot be divided

Evidence:Evidence: Chemical reactions are a Chemical reactions are a

rearrangementrearrangement of solid atoms. of solid atoms.

Studying AtomsStudying AtomsDALTON’S ATOMIC THEORY:DALTON’S ATOMIC THEORY:

Studying AtomsStudying AtomsTHOMSON’S ATOMIC THEORY:THOMSON’S ATOMIC THEORY: all matter is all matter is made of particles that made of particles that CANCAN be divided be divided

EVIDENCEEVIDENCE:: Particles collected on metal plateParticles collected on metal plate

Studying AtomsStudying AtomsTHOMSON’S ATOMIC THEORY:THOMSON’S ATOMIC THEORY: all matter is all matter is made of particles that made of particles that CANCAN be divided be divided

The particles ALWAYS had a mass 1/2000 of a The particles ALWAYS had a mass 1/2000 of a Hydrogen atom.Hydrogen atom.

The beam was always attracted to the positive The beam was always attracted to the positive sideside

Studying AtomsStudying AtomsTHOMSON’S ATOMIC THEORY:THOMSON’S ATOMIC THEORY: all all matter is made of particles that matter is made of particles that CANCAN be dividedbe divided

CONCLUSIONCONCLUSION:: These particles came from the atoms.These particles came from the atoms.

Thomson’s “plum pudding” ModelThomson’s “plum pudding” Model

Explained neutral atoms with charges

Studying AtomsStudying Atoms

RUTHERFORD’S ATOMIC THEORY:RUTHERFORD’S ATOMIC THEORY: all atoms all atoms positive charge is concentrated in the positive charge is concentrated in the nucleusnucleus

Studying AtomsStudying AtomsRUTHERFORD’S ATOMIC THEORY:RUTHERFORD’S ATOMIC THEORY: all atoms all atoms positive charge is concentrated in the positive charge is concentrated in the nucleusnucleus

Discovered:Discovered: Uranium emits fast moving positive particlesUranium emits fast moving positive particles

Studying AtomsStudying AtomsRUTHERFORD’S ATOMIC THEORY:RUTHERFORD’S ATOMIC THEORY: all atoms all atoms positive charge is concentrated in the positive charge is concentrated in the nucleusnucleus

If you shoot these positive particles at other If you shoot these positive particles at other atoms (Thomson’s plum pudding atom), what atoms (Thomson’s plum pudding atom), what would happen to the particle?would happen to the particle?

Studying Atoms – Gold Foil Studying Atoms – Gold Foil ExperimentExperiment

4.1 The Gold Foil Experiment4.1 The Gold Foil Experiment

RUTHERFORD’S ATOMIC THEORY:RUTHERFORD’S ATOMIC THEORY: all atoms positive charge is concentrated in the nucleusall atoms positive charge is concentrated in the nucleus

Studying Atoms – Modern Atomic Studying Atoms – Modern Atomic TheoryTheory

Bohr Atom:Bohr Atom: Electrons are in energy levelsElectrons are in energy levelsElectrons move when they gain or lose Electrons move when they gain or lose energy energy (example)(example)

4.2/4.3 The Structure of the Atom & Modern 4.2/4.3 The Structure of the Atom & Modern Atomic TheoryAtomic Theory

JOURNALJOURNAL: : 1.1. QUIETLY work on the “Lewis Dot QUIETLY work on the “Lewis Dot

Structures” Worksheet from the back Structures” Worksheet from the back table. Use the Periodic Table in your table. Use the Periodic Table in your book to help you.book to help you.

Parts of an ATOM:Parts of an ATOM:

Subatomic particlesSubatomic particles – – distinguished by mass, charge distinguished by mass, charge

and locationand location

Subatomic particle PROPERTIESSubatomic particle PROPERTIES Protons (p+):Protons (p+):

In the nucleusIn the nucleus Charge of 1+Charge of 1+ Mass of 1Mass of 1 DEFINES THE ELEMENT DEFINES THE ELEMENT

(equals the ATOMIC NUMBER)(equals the ATOMIC NUMBER)

Protons (p+):Protons (p+): Atoms of DIFFERENT elements Atoms of DIFFERENT elements

have DIFFERENT numbers of have DIFFERENT numbers of protonsprotons

Subatomic particle PROPERTIESSubatomic particle PROPERTIES Neutrons (n°):Neutrons (n°):

In the nucleusIn the nucleus NO chargeNO charge Mass of 1Mass of 1 Protons + neutrons = Protons + neutrons = the ATOMIC the ATOMIC

MASSMASS

Neutrons (n°):Neutrons (n°): Atoms of the same element with Atoms of the same element with

DIFFERENT numbers of neutrons DIFFERENT numbers of neutrons are called are called

ISOTOPESISOTOPES

Neutrons (n°):Neutrons (n°): ISOTOPES of Hydrogen. ISOTOPES of Hydrogen. Same Same

Atomic #, different Mass #Atomic #, different Mass #

Electrons (e-):Electrons (e-): In ENERGY LEVELS around the nucleusIn ENERGY LEVELS around the nucleus Charge of 1-Charge of 1- Mass of 1/1836 of a p+Mass of 1/1836 of a p+ Equal to the number of protonsEqual to the number of protons The outermost shell of electrons is called The outermost shell of electrons is called

the VALENCE SHELL which holds the the VALENCE SHELL which holds the VALENCE ELECTRONS.VALENCE ELECTRONS.

Take out Bohr Diagram Sheet.

Electrons (e-):Electrons (e-): Change ENERGY LEVELS when the atom Change ENERGY LEVELS when the atom

GAINS or LOSES energyGAINS or LOSES energy

The most stable electron

arrangement

Electrons (e-):Electrons (e-): CurrentTheory – CurrentTheory – “Electron Cloud Model” (p116-17)“Electron Cloud Model” (p116-17)

Orbitals that show most PROBABLE location of electronsOrbitals that show most PROBABLE location of electrons

Electrons (e-):Electrons (e-): Atoms of the same element with different Atoms of the same element with different

number of ELECTRONS are called number of ELECTRONS are called IONSIONS

IONS:IONS: form to make the outermost shell stableform to make the outermost shell stable

4.2/4.3 The Structure of the Atom & Modern 4.2/4.3 The Structure of the Atom & Modern Atomic TheoryAtomic Theory

JOURNALJOURNAL: : 1.1. QUIETLY take out your Periodic Table QUIETLY take out your Periodic Table

Basics.Basics.

2.2. STUDY FOR YOUR VOCAB QUIZ ON YOUR STUDY FOR YOUR VOCAB QUIZ ON YOUR OWN.OWN.