Fall Semester Study Guide

The 3 particles found in an atom are the proton, electron, and neutron.

Protons have a positive charge and are found inside the nucleus.

Electrons have a negative charge and are found outside the nucleus.

Neutrons have no (zero) charge and are found inside the nucleus.

The atomic mass is made up of the mass of both the proton and neutron.

Remember APE:

Atomic number = # of Protons = # of Electrons

Remember MAN:

Mass – Atomic number = Number of Neutrons

Energy Levels

The first energy level can only hold 2 electrons.

The second energy level can only hold 8 electrons.

The third energy level can only hold 8 electrons.

Molecules are made of atoms that have been joined together.

There are two types of molecules:o Elements (H2)o Compound (NaCl)

An element is when two or more of the same atoms join together.

o Example: O2 (the oxygen we breath) is made out of two oxygen atoms.

A Compound is a combination of two or more different elements (atoms).

o Example: 1 Na (sodium) atom + 1 Cl (Chlorine) atom = the compound NaCl

The example above is a compound because the molecule is made out of different atoms.

The subscript in the below example shows that in O2 there are 2 oxygen atoms.

The coefficient in 2H2O shows that there are 2 H2O water molecules.

To find the force being exerted you use the equation F = ma (F= m x a). Potential energy is stored energy or positional energy. Kinetic energy is the energy of motion. When the force acting on an object is 0N the object is balanced or not moving. When the force acting on an object is greater than zero (2N) the object is

unbalanced or moving. An object that is not moving will begin to move when it comes into contact

with an unbalanced force. A moving object will come to rest when it comes in contact with a balanced

force. To change the direction of a moving object, the object must come in contact

with an unbalanced force. When measuring the force exerted on an object if the forces are acting in the

same direction you add the forces together. 5N + 5N = 10N When measuring the force exerted on an object if the forces are acting in

opposite directions you subtract the forces. 5N - 7N = 2N The combination of all forces acting on an object is the net force. Force is a push or a pull. Force is measured in N newtons. Newtons first law explains the law of inertia. Inertia is an object resistance to a change in motion. An object at rest will remain at rest until an object or unbalanced force acts

on it. An object in motion will remain in motion until an object or unbalanced force

acts on it. The more mass an object has the more inertia it has.

Newtons second law talks about the relation between acceleration, mass, and force.

The more mass an object has the more force you will need to apply to move or accelerate the object.

Newton’s Third Law is the law of action – reaction. For every action there is an equal and opposite reaction.

Birth - Stars are born in the nebula, which are huge clouds of gas and dust. The nebula begins to contract under the pull of its own gravity. This forms a protostar.

Main Sequence Star - Stars live out the majority of their lives in a phase termed as the Main Sequence. This is the longest, most stable period of a star’s life. It converts hydrogen to helium in its core, generating heat and light.

Red Giants and Supergiants - As the nuclear fuel becomes depleted the core contracts and our layers expand.

Planetary Nebula - Now the outer layers of the star start to drift off into space. The star loses most of its mass to the nebula.

White Dwarf - The star cools and shrinks. No nuclear reactions take place and the faint star radiates it heat into space.

Black Dwarf - The star will eventually lose all its heat and energy and become dark and cold.

Supernova - The core collapses in an instant. Forces in the core overcome the gravitational forces, causing a massive, short-lived explosion.

Neutron Star - It contracts into a small star that has extraordinarily strong magnetic field, and a rapid spin.

Black Hole - It contracts and becomes a black hole. The gravitational field is so strong that even light cannot escape.

H-R Diagram - The Hertzsprung-Russell Diagram is a graphical tool that astronomers use to classify stars according to their luminosity, spectral type, color, temperature and evolutionary stage.

Spiral Galaxy – Spiral galaxies have a curved bulge in the center that is surrounded by distinct, revoloving arms. The milky way, the galaxy earth belongs to, is spiral.

Elliptical Galaxy – Elliptical galaxies are massive blobs of stars. Some are spherical in shape, while others are more oval. Elliptical galaxies contain old stars so they are the oldest type of galaxy in the universe.

Irregular Galaxy – Irregular galaxies that do not belong in the spiral galaxy or elliptical galaxy categories. Many irregular galaxies look simply like clouds of stars and nebulas.

Sun (Small or medium) Size Star - Sun Red Giants Planetary Nebula White Dwarf Black Dwarf

Huge Stars - Huge Star Red Supergiant Supernova Neutron star

Giant Stars - Giant Star Red Supergiant Supernova Black Hole