Atom

The smallest unit of matter

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Element

A pure substance made on only one type of an atom

Subatomic Particles

The small parts that create an atom, which include

protons, neutrons and electrons

Protons

Postively charged (+)

found in nucleus of an atom with a mass of 1 amu

Electrons

Negatively charged (-)

Found orbiting the nucleus

does not have mass

Neutrons

Do not have a charge (o)

Found in the nucleus

has 1 amu of mass

Atomic Number

The amount of protons an element has.

Determines how the periodic table is arranged.

Atomic Mass

Determined by the number of protons and neutrons in an atom (the nucleus)

Calculating Neutron #

Atomic Mass - Atomic #= Amount of neutrons

Example for Carbon:

12 amu-6protons = 6N

Isotopes

Formed when the neutron # is more/less than normal

Ions

Formed when atoms lose or gain electrons. Creates charged atoms/molecules

Example Na+ and Cl- are ions

Valence Electrons

# of electrons in an atoms outermost shell

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Periods

The rows in the periodic table

Indicate number of shells/orbitals an atom has

Groups

The columns in the periodic table

Indicates # of valence electrons an atom has

Reactivity

The likelihood that atoms will bond together

Bonding

Energy connections between atoms determined by the number of valence electrons

Covalent Bonds

Created when atoms SHARE valence electrons. Carbon  and other non metals creates these types of bonds

Ionic Bonds

Created when valence electrons are TRANSFERRED from one atom to another

Group 1 and 7 create these types of bonds

Noble Gases

Found in Group 8 and are NON-reactive, meaning they will not create bonds with other atoms

Highly Reactive Elements

Will most likely bond. Group 1 and 7 are highly reactive because when they combine they create a full shell

Acids

Substances with a high concentration of hydrogen ions (H+). pH range of 1-6

Strong Acid

Where most of the substance dissociates (breaks down) into H+ ions. pH range of 1-3 is a strong acid

Base (Alkaline)

Substances with a high concentration of hydroxide ions (OH-) pH range of 8-14

Strong Base

Where most of the substance dissociates (breaks down) to create OH- ions.

10 -14 pH is a strong Base

pH Scale

The measurement of the amount of H+ (hydrogen ions) found in a substance.

The scale is from 0-14 where 7 is neutral