PS+2+-+4th+Period+Brown

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Questions:

C. Protons and Neutrons D. Protons, Neutrons, and Electrons
 * 1) Which subatomic particles are found in the nucleus of an atom?
 * A. Protons and Neutrons** B. Electrons and Neutrons

2. Which of the following are not a property of most metals? A. Solid at room temperature B. Have luster C. Conduct heat and Electricity well **D. Do not readily react with any other elements**

3. Which types of elements tend to gain electrons to reach chemical stability? A. Metals **B. Nonmetals** C.Metalloids D. Noble Gases

4. Which one of the following is an example in which nuclear fusion occurs? A. Radioactive decay used to destroy cancer cells B. The splitting of U-235 in an atomic bomb D. Radioactive tracers to detect blood clots
 * C. The thermonuclear burning in stars**

5. Which subatomic particles are involved in chemical reactions? A. Protons B. Neutrons **C. Electrons** D. Nuclei

6. Why are Noble Gases stable atoms? A. They have an equal number of protons and electrons C. They form positve ions by losing valence electrons D. They form negative ions by gaining electrons
 * B. They have 8 valence electrons in their outer energy level**

7. Which of the following statements are not true about Noble Gases? A. They have full valence shell B. They do not react readily with other elements D. They are in Group 18(or VIIIA)
 * C. They usually exist as ions**

8. How many valence electrons does Silicone have? A. 14 B. 16 **C. 4** D.2

9. An ionic bond results from the transfer of electrons from: A. one orbital to another within the same atom C. the valence shell of one atom to the nucleus of another atom D. the nucleus of one atom to the nucleus of another atom
 * B. a valence shell of one atom to a valence shell or another atom**

10. What type of bond is formed when atoms transfer electrons? A. Covalent B. Hydrogen D. Polar
 * C. Ionic**

11.Why are Group 17 atoms extremely reactive? B. They want to gain two electrons to become stable C. They want to lose one electron to become stable D. Their outer shell is full of electrons
 * A. They want to gain one electron to become stable**

12.Which of the following is a characteristic of an ionic bond? A. Low melting point B. Shares electrons D. insoluble
 * C. good conductor of electricity in aqueous solution**

13. Which element has two electrons in its valence shell? A. N B. C D. O
 * C. Be**

14. Where might you find a metalloid element used? B. Kitchen potholder/ oven mitt C. Electical power lines D. Atmospheric gas mixture
 * A. Computer motherboard**

15. Which of the following statements correctly describes compounds containing covalent bonds? A. covalent compounds have high melting points B. covalent compounds conduct electricity well C. covalent compounds have high boiling points
 * D. covalent compounds tend to be brittle solids**

Name- Carbon-14 Symbol- 14 6 -atoms of these elements contain one more valence electron then the previous element -on the sun
 * The structure of Atoms**
 * Atom- the smallest unit of an element that still has the chemical properities of that element
 * Nucleus- positively charged center of an atom that contains protons and neutrons and is surrounded by a cloud of electrons
 * Subatomic Particle- small bits of matter that make up atoms, including protons, neutrons, and electrons
 * Location- nucleus is in the center of an atom, protons and neutrons are on the outside
 * Charge- protons are positive; neutrons are neutral; electrons are negative
 * Bohr Model- a model of an atom
 * Electron Cloud- area around the nucleus of an atom where the atoms electrons are most likely to be
 * Attraction- opposite charges attract
 * Repulsion- protons and protons repel; as does electrons and electrons
 * Energy Level- energy levels are areas of the cloud where the electrons are
 * Masses of Atoms**
 * Atomic number- number of protons in an atoms nucleus
 * Mass number- sum of the number of protons and neutrons in an atoms nucleus
 * Writing the mass number:
 * C**
 * Isotopes- are atoms of the same element that have different numbers of neutrons
 * Atomic Mass- the weighted average of the masses of all the naturally occurring isotopes of an element
 * Periodic Table**
 * Groups- vertical column of elements on the periodic table
 * Periods- horizontal columns
 * Valence Electrons- bonding electrons; electrons that are found in the outer most energy level from chemical bonds
 * Ions- an atom gains or loses one or more valence electrons
 * Alkali Metals- the first column on the periodic table
 * Alkaline Earth Metals- second column on the periodic table
 * Transition Metals- elements in groups 3-12
 * Boron Family- elements in group thirteen
 * Carbon Family- elements in group fourteen
 * Nitrogen Family- elements in group fifteen
 * Oxygen- elements in group sixteen
 * Halogens- elements in group seventeen
 * Noble Gases- elements in group eighteen
 * Stability-
 * Octet-
 * Periodic Trends**
 * trends across groups 1-3
 * Ions**
 * Stable- contains 8 valence electrons
 * Chemical Reaction- the number of protons and neutrons remain constant
 * Group 1- loses 1 electron
 * Group 2- loses 2 electrons
 * Group 16- gains 2 electrons
 * Group 17- gains 1 electron
 * Group 18- stable; does not gain or lose electrons
 * Nuclear Fission**
 * Nuclear Reaction- involve the particles in the nucleus of the atoms
 * Energy-
 * Fission- occurs when a heavy nucleus splits into two or more parts
 * Initiating Fission- the penetration of a large nucleus by a neutron is one way to initiate a fission reaction
 * Chain Reaction- one or more ejected neutron strikes another U-235 nucleus,another fission reaction occurs
 * Critical Mass- the mass of U-235 required for the chain reaction
 * Nuclear Fusion**
 * Fusion- occurs when more than one nuclei fuse, or combine, to form a larger single nucleus
 * Mass- the amount of matter
 * Where does nuclear fusion occur?
 * Nuclear Applications**
 * Nuclear Applications-
 * Nuclear Medecine- radioactive materials are used in medical technologies
 * Tracer- natural substances can be spiked with radioactive substances
 * Nuclear Weapons- nuclear reactions are also used in nuclear weapons
 * Nuclear Power- energy from controlled nuclear fission is used to heat water into steam



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