PS+2+-+5th+Period+Brown


 * __Properties of the Atom__**

Atom- the smallest particle of an element that still retains the properties of the element. Nucleus- positively charged center of an atom that contails protons and neutrons and it's surrounded by a cloud of electrons. Proton- positive particle, composed of quarks inside the nucleus of an atom that has a charge of 1+. Neutron- Neutral particle, composed of quarks, inside the nucleus of an atom. Electron- Particles surrounding the center of an atom that have a charge of 1-. Location/charge: - Protons: inside the nucleus (positive) - Neutrons: inside the nucleus (Neutral) - Electrons: in a cloud around the nucleus (negative) Relative Mass: -Protons weigh the same as neutrons -Protons weigh more than electrons
 * __Structure of Atoms__**

Bohr Model:

Repultion: like charges repel. Attraction: opposite charges attract. Electron Cloud: the area around the nucleus of an atom where the atoms electrons are most likely to be found. Energy Level: The levels levels of energy around the atom. The levels nearer the nucleus have less energy, and the levels farther from th enucleus have more energy.

Subatomic Particles: Protons, neutrons, and electrons. Atomic Numbers: Number of protons in an atom's nucleus. Mass Number: The sum of the number of protons and neutrons. Writing mass Number:
 * __Masses of Atoms__**

Isotopes: Atoms of the same element that have differetn numbers of neutrons. Atomic Mass: Weighted mass of the mixture of an elements isotopes.

Arrangement: Elements often are sorted or grouped according to the properties. Groups: Verticle columns in the Periodic Table. Periods: Horizontal rows in the Periodic Table. Valence Electrons: The outermost electrons of an atom. These electrons are used for chremical bonding. Ions: Charged Particle that has either more or fewer electrons than protons. Alkali Metals: The first group in the Periodic Table. They are shiny, malleable, and ductile. Alkali Earth Metals: The second group of the Periodic Table. Transition Matals: Elements in groups 3-12 in the Periodic Table. They are less reactive, and harder metals. Boron Family: Elements in group 13. Carbon Family: Elements in group 14. Nitrogen Family: Elements in group 15. Halogens: Elements in group 17. Noble Gases: Elements in group 18, they are very reactive, and they have a full valence shell. Stability: An element is stable when it's valence shell is full. Octet rule: Atoms tend to gain, lose or share electrons so as to have eight electrons in their outer electron shell.
 * __The Periodic Table__**

Stable: An atom with 8 valence electrons. Chemical Reaction: Changes the atom, but not nesessaraly the appearence. Atoms gain, lose, or share electrons to become stable.
 * __Ions__**

Chemical Reactions: Only the electrons are involved and the nucleus remains intact. Nuclear Reactions: Involve the particles in the nucleus of the atom. Energy: There is a great deal more energy involved in nuclear reactions than in chemical reactions. Fission: Nuclear fission occurs when a heavy nucleus splits into two or more parts, when an atom splits, a large amount of energy is released. Intiating Fission: The penetration of a large nucleus by a neutron is one way to initiate a fission reaction. Chain Reaction:If 1 or more ejected neutron strikes another large nucleus, another fission reaction may occur. Critical Mass: Critical mass is the amount of fissionable material required so that each fission reaction produces approximately one more fission reaction.
 * __Nuclear Fission__**
 * Nuclear Fission occurs in nuclear power plants*

Fusion: Reaction in which two or more atomic nuclei from a nucleus combine to form a larger nucleus with a larger mass.
 * __Nuclear Fusion__**
 * Fusion occurs on the sun*

__**Nuclear Applications** Nuclear Mecicine__: One form of nuclear mecicine is Radiation. Radiation can be used to destroy targeted cells such as cancer cells. __Nuclear Weapons__: Nuclear reactions are also used in weapons such as atomic bombs. Some drawbacks of nuclear weapons is that when used it can severly contaminate the enviornment. __Nuclear Power Reactors__ In a nuclear power reactor, controlled nuclear fission is used to heat water into steam, which then turns a huge magnent, which creates electricity.


 * __Helpful Websites__**
 * [|www.webelements.com]
 * [|www.science-park.info]
 * [|www.chemicool.com]
 * [|www.ansto.gov.au/nuclear_information/what_is_nuclear_science]
 * [|www.library.thinkquest.org/3471/nuclear_energy.html]


 * __Practice Questions__**:

1.   Which of the following particles of an atom have a positive charge? a.   Protons b.   Neutrons c.   Electrons d.   Electron shells 2.   Which of the following parts of an atom has a negative charge? a.   Protons b.   Neutrons c.   Electrons d.   The Nucleus 3.   Which of the following parts of an atom has no charge? a.   Protons b.   Neutrons c.   Electrons d.   The Nucleus 4.   Which subatomic particles are found in the nucleus of an atom? a.   Protons and electrons b.   Electrons and neutrons c.   Protons and Neutrons d.   Protons, neutrons, and electrons 5.   Lithium and sodium are in the same group of elements in the periodic table. Which of the following statements is true regarding these two elements? a.   They have the same number of electrons in their valence shell b.   They have the same number of protons in their nucleus c.   They are both Noble gases d.   They have different chemical properties 6.   Which of the following statements is **__not__** true of noble gases? a.   They have a full valence shell b.   They do not react readily with other elements c.   They usually exists as ions d.   They are in group 18 (or VIIIA) 7.   What is the most common charge of an oxygen ion? a.   +1 b.   +2 c.   -1 d.   -2 8.   The alkali earth metals are in group 2. What is the charge of a (Ca) calcium ion? a.   +1 b.   +2 c.   -1 d.   -2

9.    What are Isotopes? a.   Elements with the same mass number b.   Elements with the same atomic mass c.   Elements with the same number of protons and electrons, but different number of neutrons d.   Elements with the same number of protons and neutrons, but a different number of electrons. 10.   Where would you find a nuclear fusion reaction occurring? a.   In a nuclear reactor b.   In the sun c.   In an X-ray machine d.   In a microwave oven 11.   The sun is a good example of what kind of reactor? a.   A spontaneous fission reactor b.   An induced fission reactor c.   A fusion reactor d.   A supercritical fission reactor 12.   Which subatomic particle is used as a projectile to induce fission reactions? a.   The proton b.   The neutron c.   The electron d.   The alpha particle 13.   Fission fragments are the result of    a.    Fusion only b.   Fission only c.   Supercritical fission only d.   A and B

Answers: 1. A 2. C 3.B 4.C 5.A 6.C 7.D 8.B 9.C 10.B 11.C 12.B 13. B