Chapter 12 the Nucleus of the Atom

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The Nucleus of the Atom

Chapter 12

Great Idea:

Nuclear energy depends on the conversion of

mass into energy

Chapter Outline

Empty Space, Explosive Energy

The Organization of the Nucleus

Radioactivity

Energy from the Nucleus

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mp y pace,

Explosive Energy

Empty Space,

Explosive Energy

Relation of atom to nucleus a goes on n e nuc eus

has almost nothing to dowith the atoms chemistry,and vice versa

The energies available in thenucleus are much greaterthan those available amongelectrons

E=mc2

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e rgan za on

of the Nucleus

The Organization

of the Nucleus

Rutherford

Nucleus

Proton

neutron

Nucleus gives atom its mass

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Atomic Numbers, Isotopes,

and the Mass Number

Atomic number # of rotons in

nucleus Defines chemical

behavior

Isotopes Elements with

different numbersof neutrons

Mass number Total protons and

neutrons

The Strong Force

Strong force

Holds nucleus together

Operates over short distances

Binding energy

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Radioactivity

Whats Radioactive?

Radioactivity or radioactive decay

Radiation

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The Kinds of

Radioactive Decay

Alpha Decay

Composed of 2 protonsand 2 neutrons

Beta Decay Emission of electron

Neutrino

Weak Force

Gamma Radiation Electromagnetic

radiation

Moving Down the Chart

of the Isotopes

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Radiation and Health Ionization

Long-term effects

Cancer

Birth defects

Half-Life

Half-life

Average time for decay of batch ofradioactive isotopes

Wide range of half-lives Cannot predict half-life

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Radiometric Dating

Radiometric dating

Measurement of half-life

Carbon-14

Half-life = 5700years

Geology

Need longer half-lives

Decay Chains

Decay chains

Series of deca s

Continues until stable isotope appears

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Indoor Radon

Decay of Uranium-238

Radon-222

Can build up

Increase ventilation

Energy from the Nucleus

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Nuclear Fission

Fission

Splitting of nuleus

Nuclear Reactor

Extracts energy

Meltdown

Fusion

Fusion

2 atoms of H combineto form He

Some massconverted to energy

Sunli ht