Is specifically defined as a force

acting through a distance.

Any Action on an object that can cause

the object to change speed or direction.

(i.e., Push or Pull)

Electrical

Nuclear

Acoustical (sound)

Radiant (light)

• Definite shape & volume
• Molecules or ions are held in place by strong attractive forces
• Molecules have thermal energy, but not enough to overcome attractive forces
• Molecules are arranged in a orderly, fixed pattern

• Shape indefinite
• Volume definite
• Forces between the molecules are not strong enough to hold a definite shape.

• Shape Indefinite
• Volume indefinite
• Large amount of space between molecules because of their high thermal energy

• Building block of matter is the atom
• Positively charged surrounded by negatively charged shells
• Central core, called the nucleus, contains protons & neutrons
• Shells are formed by electrons which exist in structured orbits around nucleus

• Positively Charged (+1)
• Mass: 106726E-24 gm or 1.007276470 amu
• Each element is determined by the number of          in it's nucleus
• All atoms of the same element have the same number of        

• Neutrally charged (0)
• Mass: 1.6749E-24 gm or 1.008665012 amu
• The number of           determines the isotope of an element

• Negatively charged (-1)
• Small Mass: 9.1085E-28 gm or 0.00054858026 amu
• Because the mass of an          is so small, virtually the entire mass of an atom is furnished by the nucleus.
• The number of           is normally equal to the number of protons. Therefore the atom is electrically neutral

• The number of protons in the nucleus of an element
• i.e., A hydrogen atom contains one proton in the nucleus. Therefore, the             of hydrogen is 1
•               is often represented by the symbol Z

• The total number of protons plus neutrons in the nucleus of a particular isotope of an element
• i.e., A helium atom has 2 protons + 2 netrons, which means it has a             of 4.

• The             of an atom of a particular isotope
• i.e., the mass of one C-12 atom is exactly 12 amu.

The weighted average of the isotopic masses of an element, based on the percent abundance of it naturally occurring isotopes.

• The columns or vertical sections in the Periodic Table
• The elements also behave chemically similar; that is they have similar chemical properties

• The highest occupied energy level in a ground-state atom
• Max of eight electrons
• The number of electrons in the            determines the chemical behavior or properties of the atom

• The electrons that reside in the Valence Shell
• There is a max of eight electrons in this shell.