About Atoms

Explores club

Ray Jackson

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Atoms

Basic building block of matter The center of an atom is its nucleus

– The nucleus contains subatomic particles Positively charged protons Uncharged neutrons

– The nucleus is surrounded by Negatively charged subatomic particles called electrons

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An Atom

e l e c t r o n

n e u t r o n

p r o t o n

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Atoms

Positively charged protons usually equal the number of negatively charged electrons– Oppositely charged protons and electrons are

attracted to each other– Exert a pulling force

+ -Proton Electron

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Atoms and Chemical Elements

Periodic Table of the Elements– Shows 92 chemical elements of which 90 occur

naturally in nature– The atomic number of each element is the

number of protons in its nucleus Hydrogen—(atomic number 1) has 1 proton and 1

electron and no neutrons Oxygen—(atomic number 8) has 8 protons and 8

electrons and 8 neutrons

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Hydrogen and Oxygen Atoms

Hydrogen

Oxygen

+P-E+P+P

+P+P +P+P+P+P

-E

-E

-E -E

-E-E

-E

-E

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Atoms and Molecules

A molecule is the tiniest part of any substance and consists of one or more atoms– Water molecule—2 hydrogen atoms and 1

oxygen atom The chemical formula for water is H2O

– Sugar molecule—12 carbon atoms, 22 hydrogen atoms, and 11 oxygen atoms The chemical formula for sugar is C12H22O11

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Atoms and Energy

An outside force upsets the balance between positively charged protons and negatively charged electrons generating an electrical charge or heat energy– Electrical energy– Nuclear energy– Radiant energy

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Sources “What is Electricity,” U.S. DOE Energy Kid’s Page,

http://www.eia.doe.gov/kids/energyfacts/sources/electricity.html (accessed May 15, 2006).

“Nuclear Energy (Uranium) Energy from Atoms,” U.S. DOE Energy Kid’s Page, http://www.eia.doe.gov/kids/energyfacts/sources/non-renewable/nuclear.html (accessed May 15, 2006).

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Sources “Atom,” Wikipedia, November 6, 2004,

http://en.wikipedia.org/wiki/Atoms (accessed May 15, 2006).

“All About Atoms,” Jefferson Lab, http://education.jlab.org/indexpages/index.html (accessed May 15, 2006).

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