Maybe I should be wearing goggles CHEMISTRY

Chemistry Pre-Test What is matter? Name the particles of the atom List the CHARGES of each particle How do we determine the Atomic Number of an element? How do we determine the Atomic Mass of an element? Name at least five (5) elements and their symbols

What is Matter? 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, non-Newtonian, & 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

Nitrogen 2 7 5 N 14.0067 Elemental Symbol (Often from Latin or Greek) (1st letter is upper case, 2nd is lower case) Nitrogen 2 7 5 N 14.0067 Elemental Name # of e- in each electron cloud Atomic Number (# of P+) Atomic Mass (# of P+ & N=)

Q: How can I calculate the number of neutrons in an element??

Elemental Names & Symbols 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

Cl Na