Transcript Chemistry Presentation: Part One

Maybe I
should be
wearing
goggles
CHEMISTRY
Chemistry Pre-Test
1. What is matter?
2. Name the particles of the atom
3. List the CHARGES of each particle
4. How do we determine the Atomic Number of an
element?
5. How do we determine the Atomic Mass of an
element?
6. Name at least five (5) elements and their symbols
What is Matter?
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Anything that can be smelled, tasted, touched…
Has mass and volume (takes up space)
Matter exists in a state or phase
Phases of matter include solid, liquid, gas, nonNewtonian, & plasma
Common Phases of Matter:
Solid, Liquid, Gas
Non-Newtonian
substances
sometimes behave
like a solid and
sometimes like a
liquid
Plasmas consist
of freely moving
charged particles,
(electrons & ions)
It is perhaps the
most common
phase of matter in
the universe
Matter is made up of atoms…
What’s an Atom?
• The word ATOM (átomos) was first used by the
Greek philosopher Democritus
• Atom translates to “Indivisible”
• It is the smallest particle characterizing an element
• We can’t see the parts of atoms, even with modern
technology, so we have an Atomic Theory
• A theory is a good, logical idea about something
but it hasn’t been proven to be true
Democritus
460-370 BCE
Atomic Theory
It’s thought that atoms are made of
these common particles:
• PROTON- has a positive Charge (P+)
• NEUTRON- has a neutral charge; has
both positive and negative attributes (N=)
• ELECTRON- has a negative charge (e-)
Atomic Structure
Proton
Nucleus
Neutron
electron
Electron Clouds
Benfey’s Periodic Table 1960
Stowe Periodic Table 1988
Mayan Periodic Table 2001
Spiral Periodic Table 2005
Dufour Periodic Table
There is no single periodic table…
Most Common Periodic Table
• First organized using the known properties from
other chemists like Stanislao Cannizzaro
• Dmitri Mendeleev created the most commonly used
table of elements in 1869
Mendeleev’s table 1869
Most Commonly Used Table
Period of elements
• Organized horizontally
• Indicates # of electron levels
Family of elements
• Organized vertically
• Indicates # of electrons in outer
cloud
Elemental Symbol (Often from Latin or Greek)
(1st letter is upper case, 2nd is lower case)
Nitrogen
# of e- in
each
electron
cloud
2
5
7
N
14.0067
Elemental
Name
Atomic Number (# of P+)
Atomic Mass (# of P+ & N=)
Q: How can I calculate the
number of neutrons in an
element??
Elemental Names & Symbols
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Fe
Iron; Latin Ferrum meaning “firm”
Cu
Copper; Greek for island of Cypress/ Cuprius
Na
Sodium; Natrium (Latin) meaning “soda”/
“salt”
• Ag
• Silver; from Latin Argentum meaning “bright”
More Elemental Names & Symbols
• Au
• Gold; (Latin) Aurum- Roman Goddess of
dawn
• Hg
• Mercury; Greek Hydragyrium meaning ‘liquid
silver’
• Pb
• Lead; Latin for Plumbum; origin of ‘plumber’
Element song?
http://www.privatehand.com/flash/elements.html
John Dalton
September 6, 1766 – July 27, 1844
• All matter is
made of atoms
• Atoms of an
element are
identical
• Atoms are
rearranged in
reactions
Elements are individual atoms…
• When elements join together a compound
forms
• Elements join forming molecules of a
compound
• There several ways for molecules to
form…
Covalent Bonding
• Atoms join together to form molecules of
a compound through bonding
• Atoms “prefer” to have 8 e- in the outer
cloud
• In order to become more stable, elements
will share e• Water (H2O) is an example of covalent
bonding
H
H
O
Ionic Bonding
• Occurs with salts
• One element gives up an electron while
another gains an electron
• In the case of Sodium Chloride, Na gives up
an electron and Cl gains one
• This creates ions: the Na atom has a positive
charge & the Cl atom has a negative charge
• Opposite charges attract and a compound is
formed
Na
Cl