Basic Chemistry for

Earth Science

The Periodic Table

• Family/Group: vertical columns

• Period: the horizontal rows on the periodic table

• Elements are pure substances that cannot be broken down into a more simple substance. They are found on the periodic table.

• An atom is the smallest part of an element you can have and still have the properties of that element.

• All atoms are make-up of subatomic particles. The 3 subatomic particles are:– Protons– Neutrons– Electrons

• The nucleus is the center of an atom.

• Protons have a positive charge and are found in the nucleus.

• Electrons have a negative charge and are found in a “cloud” outside of the nucleus.

• Neutrons are neutral and are found in the nucleus. • The number of protons determine the identity of an element. • The Atomic Number tells you the number of protons and electrons

(unless it is an ion).

• The Mass Number tells you protons + neutrons.

• Neutrons = Mass Number - # of Protons

Element Mass # Atomic # Protons Electrons NeutronsGoldMagnesiumAluminumCalciumSodium

• An Isotopes are atoms of an element that have the same number of protons, but a different number of neutrons.

Element Mass # Atomic # Protons Electrons Neutrons

Carbon 12 6

Carbon 14 6

• A ion is an atom that has gained or lost electrons. If an atom loses electrons it is metal. If an atom gains electrons it is non-metal.

Element Mass # Atomic # Protons Electrons Neutrons Charge

Calcium

Chlorine

Nitrogen

Metals Nonmetals

• A compound is two or more elements chemically combined. – Examples:

• Water H2O• Table Salt NaCl• Baking Soda Na2CO3

• Vinegar HC3H3O2

• A molecule is the smallest part of a compound that you can have and still have the properties of the compound.

• A mixture is a material system made up by two or more different substances which are mixed but are not combined chemically.

• A covalent bond is a bond formed when electrons are shared.

• An ionic bond is a bond formed when electrons are either gained or lost from one element to another.

A metallic bond is a bond formed when electrons are shared in large amounts.

• -like a sea of electrons that are shared by all atoms

• Ionic Bonds are like TYRANTS. They take what they want.

• Covalent Bonds are like socialists. They share what they need.

• Metallic Bonds are like Anarchists. They run around sharing what they need, but with no thought of ownership.