THE ATOM

By: Adriana Venegas

THE ATOM

WHAT IS AN ATOM

• The atom is the fundamental unit of which

elements are composed.

• Atoms are tiny particles, i.e. Hydrogen the

smallest atom, has a diameter of 10⁻⁸ cm.

• All objects are composed/made up of

atoms.

ELEMENTS

• There are over 110

types of atoms.

• Different types of atoms

are called Elements.

• Elements are organized

on a table, called

Periodic Table of

Elements

• Most common types of

elements: Hydrogen,

Nitrogen, Oxygen.

• Elements have symbols

or a set of abbreviations.

THE ANATOMY OF THE ATOM

• There are different particles in an atom.

• The Nucleus – contains both protons and neutrons.

• Protons – have a positive electrical charge.

• Neutrons – have no charge, therefore are neutral.

• Electrons – have a negative electrical charge.

• Regular atoms are electrically neutral.

• Electrons and protons counteract each other.

• In an electrically neutral atom there are the same amount of Electron

and Neutrons.

• Nucleus accounts for the nearly all of the atom’s ass.

STRUCTURE

• Nucleus located at

the center.

• Nucleus densest part

of atom.

• Electrons fall in

electron cloud.

• Electrons orbit in

energy levels.

• Exact location of

electrons cannot be

stated.

COMPOUNDS

Compound: A substance composed of a given combination of

elements that can be broken down into those elements by chemical

methods.

• This means atoms group together to form a substance.

• For example: Water, H₂O, is made up of 2 Hydrogen atoms and 1 Oxygen

atom.

• Compounds always contain atoms of different elements.

• A compound always has the same composition.

• By contrast, a pure substance, contains atoms of only that same element.

DALTON’S ATOMIC THEORY

English scientist, John Dalton presented a theory for a set of

observations in 1808.

1. Elements are made of tiny particles called atoms.

2. Atoms of an element are all identical.

3. Atoms from a given element differ from other atoms of another element.

4. Compounds are formed when atoms of one element bond with atoms of another element.

5. During chemical processes atoms are not visible. The atoms change their grouping, but are not created nor destroyed.

PHYSICAL AND CHEMICAL PROPERTIES & CHANGES

Physical Properties • Odor• Color• Volume• State: Gas, Liquid,

Plasma, Solid• Density • Melting & Boiling Point

Chemical Properties• Ability to form new

substances• A substance changes to

a new or different substance(s).

THE ENDThank you very much.

WORKS SITED

Zumdahl, Steven S., and Donald J. DeCoste. Introductory Chemistry: A Foundation: Special Edition for Salt Lake Community College. 7th ed. Mason: Cengage Learning, 2011. Print.

"Anatomy of the Atom." (EnvironmentalChemistry.com). N.p., n.d. Web. 06 May 2013. http://environmentalchemistry.com/yogi/periodic/atom_anatomy.html

"The Atom." ThinkQuest. Oracle Foundation, n.d. Web. 06 May 2013. http://library.thinkquest.org/17940/texts/atom/atom.html