Atoms, Elements, and Molecules…..Oh My!

Matter•Anything that has mass and

takes up space–Mass: How much matter is in an

object–Volume: How much space an object

takes up

Atoms•Smallest basic unit of matter

•Basic building blocks of matter

•1 tsp of H20 contains

approximately 500,000,000,000,000,000,000,000 atoms

Parts of an Atom• Nucleus—the center of

the atom, composed of protons and neutrons

• Protons—located inside the nucleus and have a POSITIVE charge

• Neutrons—located inside the nucleus and have NO charge

• Electrons—located outside the nucleus and have a NEGATIVE charge

Particle Electrical Charge

Symbol Atomic MassUnit

(AMU)

Location in Atom

Proton 1 amu

n/a 1 amu nucleus

negative 0

Check what you know…*Draw the table *Fill in the empty boxes

Elements•Characteristics are determined by the structure of its atoms

•Each element is made up of atoms that differ from every other element

Element Features

1. Atomic number—describes the number of protons in the nucleus of an atom– No two elements have the same atomic number– Atomic number also equals the number of electrons in an atom

2. Atomic Mass—is equal to the number of protons plus the number of neutrons in the atom’s nucleus

3. Chemical Symbol—is a code composed of one or two

letters that represents an element– Each element has its own chemical symbol– Example: C= carbon, Fe = iron

2 Rules1. Protons + Neutrons = the atomic mass P + N = AM

2. Protons, Electrons, and the Atomic Number are always the same number

If you know one of the numbers, you know all 3

Element Symbol

Protons Neutrons Electrons Atomic Mass

Carbon 6 6Oxygen 8 16 amuSodium 11 22 amuPotassiu

m19 20

Iron 26 56 amu

Check what you know…*Draw the table* Fill in the empty spaces

Molecules

• Two or more atoms bonded or combined together

• Can be made up of atoms that are different or atoms that are alike– Example: water is a combination

of different atoms—2 hydrogen atoms and 1 oxygen atom written (H2O)

– Example: Oxygen Gas molecules are 2 Oxygen atoms bonded together written O2