What is the smallest unit of matter? An atom What is an atom made of? Subatomic particles protons (p + ) – positive charge neutrons (n) – no charge (neutral) electrons (e - ) – negative charge
Atomic Structure Nucleus (center)
Another way to represent an atom
Reminder: Atoms are vibrating, energetic things! + ++
Let’s Look at the Periodic Table 6 C Carbon 12 Atomic Number Atomic Symbol Atomic Mass
Atomic Number 6 C Carbon 12 Atomic Number # of protons in an atom # of electrons in an atom # of protons = # of electrons
Overall, do atoms have a charge? No! For All Atoms: # of positive charges = # of negative charges
Atomic Mass 6 C Carbon 12 Atomic Mass 1 proton = 1 amu 1 neutron = 1 amu Atomic Mass = # protons + # neutrons Using only the periodic table, how can you figure out the number of neutrons in an atom?
Calculating # of Neutrons Atom: Lithium (Li) Atomic Number: _3_
Calculating # of Neutrons Atom: Lithium (Li) Atomic Number: _3_ How many protons does one lithium atom have? _____
Calculating # of Neutrons Atom: Lithium (Li) Atomic Number: _3_ How many protons does one lithium atom have? _3_
Calculating # of Neutrons Atom: Lithium (Li) Atomic Number: _3_ How many protons does one lithium atom have? _3_ Atomic Mass: ___
Calculating # of Neutrons Atom: Lithium (Li) Atomic Number: _3_ How many protons does one lithium atom have? _3_ Atomic Mass: _7_ How many neutrons does lithium have? ___
Calculating # of Neutrons Atom: Lithium (Li) Atomic Number: _3_ How many protons does one lithium atom have? _3_ Atomic Mass: _7_ How many neutrons does lithium have? _4_
Drawing Atoms: Lithium (Li) Energy Levels (Shells): Start from the inside and move out as you need to Level/Shell 1: holds up to 2 e - Level/Shell 2: holds up to 8 e - Level/Shell 3: holds up to 8 e - 3 p + 4n An electron (e-)
Drawing Atoms: Lithium (Li) Energy Levels (Shells): Start from the inside and move out as you need to Level/Shell 1: holds up to 2 e - Level/Shell 2: holds up to 8 e - Level/Shell 3: holds up to 8 e - 3 p + 4n
Lithium p + 4n