November 29, 2016 Objective: To calculate the numbers of protons, neutrons, and electrons in an atom using the periodic table Describe the structure of at atom Journal: We are starting a new unit on basic chemistry. What do you think we are going to learn about?

Chemistry – Atoms

Atoms The smallest particle into which an element can be divided and still be the same substance All living things are made of atoms

Subatomic Particles Protons: Neutrons: Electrons: Positively charged Located in the nucleus Neutrons: No charge (neutral) Electrons: Negatively charged Located in the electron cloud (orbitals)

Electron Configuration The location within the electron cloud where the electrons are most likely to be found 1st shell holds maximum of 2 electrons All other shells hold a maximum of 8 electrons

Atomic Structure

Periodic Table

Elements on the Periodic Table

Atomic Number Biggest size number in each box when looking at the periodic table Atomic Number = Number of Protons = Number of Electrons

Atomic Weight The total number of protons and neutrons added together Small number underneath the symbol when looking at the periodic table

How to find numbers of… Number of protons = Atomic Number Number of electrons = Atomic Number Number of neutrons = Atomic Weight – Atomic Number *Round atomic weight to the nearest whole number before subtracting

Valance Electrons The number of electrons in the outer shell. Used for bonding

Octet Rule When bonding, each atom wants to have a full outer shell (8 valance electrons) ***Exception is Hydrogen, which can only hold two electrons in its outer shell