Thursday, April 12, 2007

To do Chapter 5

4/12/07

What are electrons?
Negatively charged particles are called?

What are cathodes?
What is the law of electrical attraction and repulsion?
What is static electricity?
How are electrons involved in static electricity?

What was JJ Thompson’s, Bohr’s, and Rutherford’s contribution to atomic models?
What are isotopes and neutrons?
Neutrons have a ___ charge
How do S and P energy levels differ?

What are electron energy levels

Due by End on marking period 2

Exam on questions before end of marking period.
Matching page 61
Multiple choice 1-25 61 and 62

Tuesday, March 20, 2007

For test on Chapter 4 Mixtures and compound

Topics and questions for testComposition of MatterLaw of definite proportionsChemical FormulasSeparating MixturesMixtures vs. Compounds• One of the fundamental observations of modern chemistry, the law of definite proportions states that, in Compounds, the elements combine in proportion with each other, by mass.• An equivalent statement is the law of constant composition, which states that all samples of a given chemical compound have the same elemental composition• • Chemists describe compounds using formula in various formats. For molecules, the formula for the molecular unit is shown. For polymeric materials, such as minerals and many metal oxides, the empirical formula is given, e.g. NaCl for table salt. The order of the elements in molecular and empirical formulas is C, then H and then alphabetical. Trifluoroacetic acid is thus described as C2HF3O2. More descriptive formulas convey structure information, illustrated again with trifluoroacetic acid. CF3CO2H. On the other hand, formulas for inorganic compounds often do not convey structural information, as illustrated by H2SO4 for a molecule that has no H-S bonds. A more descriptive presentation would be O2S(OH)2.• A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. The ratio of each element is usually expressed by chemical formula. For example, water (H2O) is a compound consisting of two hydrogen atoms bonded to an oxygen atom.• The atoms within a compound can be held together by a variety of interactions, ranging from covalent bonds to electrostatic forces in ionic bonds. A continuum of bond polarities exist between the purely covalent bond (as in H2) and ionic bonds. For example H2O is held together by polar covalent bonds. Sodium chloride is an example of an ionic compound.Do this•


How do compounds and mixtures differ?

How do compounds and mixtures differ?

How do covalent and ionic bonds differ?

How do inorganic and organic compounds differ?

What is the rule for chemical formulas?

Friday, February 02, 2007

Pivotal question for chapter 3 for exams

  1. What are physical properties?
  2. Give examples of physical properties of five elements
  3. Compare the physical properties of metals and non-metals
  4. What are chemical properties?
  5. How are chemical symbols determined?
  6. Describe the structure of the atom
  7. Places for info
  8. http://www.usoe.k12.ut.us/curr/science/sciber00/8th/8thintro.htm
  9. http://www.chemistrycoach.com/tutorial.htm
  10. http://www.usoe.k12.ut.us/curr/science/sciber00/8th/matter/sciber/intro.htm

Spring 2007 Assignments

Science Investigations SPRING 2007
Date: 12/14/2006
To: 2nd, 3rd Coop A and B
Cc:
From: JGS 718 408 3942
RE: Assignments for term
Chapter 3
Composition of Matter Elements Page 28 in Physical Science Text
Define Words on page 36
Do Multiple Choice, Matching, Modified True and False, and Test Your Knowledge pgs 37-39

Chapter 4
Composition of matter Compounds and mixtures Page 42 in Physical Science Text
Define Words on page 47
Do Multiple Choice, Matching, Modified True and False, and Test Your Knowledge pgs 48-50

Chapter 5
Page51 in Physical Science Text
Define Words on page 60
Do Multiple Choice, Matching, Modified True and False, and Test Your Knowledge pgs 61-64

Wednesday, January 03, 2007

End Term Assignment 2007

Science Investigations December 2006
Date: 12/14/2006
To: 2nd, 3rd Coop A and B
Cc:
From: JGS
RE: Assignment Number 4 Work Machines
Work and Machines Page 345 in Physical Science Text
Define Words on page 355
Do Multiple Choice and other questions 355- 358
Text Physical Science Work Text

Thursday, November 30, 2006

Study Sheet for quiz on December 8 th Coop A

H.S. 505
James Sylvester RN
Hillcrest High School
160-05 Highland Avenue
JAMAICA ESTATES, NY 11432
Phone: (718) 658-5407 Fax: (718) 739-5137


Periodic Table first discovered in 1869 by Dmitry I. Mendeleyev is a way of presenting all the elements so as to show their similarities and differences. The elements are arranged in increasing order of atomic number(Z) as you go from left to right accross the table. The horizontal rows a called periods and the vertical rows, groups.A noble gas is found at the right hand side of each period. There is a progression from metals to non-metals across each period. Elements found in groups (e.g. alkali, halogens) have a similar electronic configuration. The number of electrons in outer shell is the same as the number of the group (e.g. lithium 2·1).The block of elements between groups II and III are called transition metals. These are similar in many ways; they produce colored compounds, have variable valency and are often used as catalysts. Elements 58 to 71 are known as lanthanide or rare earth elements. These elements are found on earth in only very small amounts.Elements 90 to 103 are known as the actinide elements. They include most of the will known elements which are found in nuclear reactions. The elements with larger atomic numbers than 92 do not occur naturally. They have all been produced artificially by bombarding other elements with particles.

FAMILIES OF ELEMENTS With so many elements, it is impractical to being a study of each one individually. The elements here will first be classified generally as metals and nonmetals. Metals will be further divided into alkali and alkaline earth metals. Metalloids will be discussed as elements with intermediate properties or metals and nonmetals, with metals on the left side of the periodic table and metals on the right. Two special classes of elements with special properties discussed are noble gasses, which combine with almost no other elements, and rare-earth elements that are so similar to one another that they are extremely difficult to separate.
Alkali Metals are the elements in Group IA of the periodic table. The members of the family are lithium, sodium, potassium, rubidium, cesium, and francium. All six elements have the properties of metals except they are softer and less dense. They can be cut with a knife. They are the most reactive metals. They are so reactive that they are never found in nature. They are always combined with other elements. The alkali metals have only one electron in their outermost shell, so alkali metals form positive ions.
Alkaline Earth Metals are beryllium, magnesium, calcium, strontium, barium, and radium. These elements, which are harder and more dense than the alkali metals, also have higher melting points and boiling points. They are highly reactive, but not as active as the alkali metals. Like the alkali metals, the alkaline metals are never found free in nature. The alkaline earth metals have two electrons in their outermost energy level, so they also form positive ions.
Transition Metals have properties similiar to one another and to other metals, but their properties do not fit in with those of any other family. Most transition metals are excellent conductors of heat and electricity. Most have high melting points and are hard. Transition metals are much less active than the alkali and alkaline earth metals. Many transition metals combine chemically with oxygen to form compounds called oxides. Many transition metals have more than one oxidation number. Transition metals form compounds that are brightly colored.
From Metals to Non-Metals in groups IIIA to VIA of the periodic table elements have properties which change from metallic to nonmetallic. These groups include the boron family, carbon family, nitrogen family, and oxygen family.
Boron, the first element in the boron family is a metalloid. Aluminum, which is right beneath boron, is by its position a metalloid. But the properties of aluminum are usually those of metals. The other members of the boron family ...gallium, indium, and thallium, are metals. Boron, which is hard and brittle, is never found in nature in the free state. It is usually found combined with oxygen. The compound boric oxide is important in making heat-resistant glass. Boric acid is commonly used as eyewash and antiseptic. The compound borax is useful as a cleaning agent and water softener.
Aluminum is the most abundant metal and the third most abundant element in the earth's crust. Aluminum is found as aluminum oxide in the ore called bauxite. Aluminum is extremely valuable in industry. It is light, strong, and does not tarnish in air. It is a good conductor and is used in wiring, airplane parts, household items.
The Carbon family includes the elements carbon, silicon, germanium, tin, and lead. Carbon can combine with other elements in a great variety of ways. Millions of carbon compounds called "organic compounds." Carbon is called the basis for life because all living things contain organic compounds.
Silicon is the second most abundant element in the earth's crust. Silicon is used in glass and incement. It is also used in solar cells. Solar cells convert the energy of sunlight into electric energy.
Germanium is a metalloid used in transistors. Transistors are devices found in many electronic instruments, such as radios and televisions. Tin is a metal which resists rusting and corrosion. The most dense element in the carbon family is the metal lead.Lead forms poisonous compounds.
The Nitrogen family consists of nitrogen, phosphorus, arsenic, antimony, and bismuth. Nitrogen and phosphorus are nonmetals. Arsenic is a metalloid with mostly nonmetallic properties. Antimony is a metalloid with mostly metallic properties. Bismuth is the most metallic element in the family. All members of the nitrogen family have five electrons in their outermost energy level. These elements lose electrons easily.
The Oxygen family includes oxygen, sulfur, selenium, tellurium, and polonium. All of these have six electrons in their outermost energy level. Their properties go from nonmetallic in oxygen and sulfur to metalloid in selenium and tellurium to metallic in polonium.
Halogens are the elements in family VIIA. They are strongly nonmetallic. The halogens include fluorine, chlorine, bromine, iodine, and astatine. They are the most active nonmetals. The chemical reactivity of the halogens is due to the number of electrons in the outermost energy levels of their atoms. Fluorine is the most active halogen. They have low melting points and boiling points. In the gas phase they exist as diatomic elements. Halongens combine readily with metals to form a class of compounds known as salts.
Noble Gasses are colorless gasses that are extremely unreactive. Because do not readily combine with other elements to form compounds, the noble gasses are called inert. The family of noble gasses includes helium, neon, argon, krypton, xenon, and radon. All the noble gasses are found in small amounts in the earth's atomsphere. One important property of the noble gasses is their inactivity. They are inactive because their outermost energy level is full.

Discovery Physical Science Link

http://school.discovery.com/lessonplans/physci.html

Monday, November 20, 2006

HW # 3 Questions Physical Science

  1. What is the conservation of energy theory?
  2. How do kinetic and potential energy differ?
  3. How can frequency and wavelength be descibed?
  4. What is the work-energy theorem?
  5. How does a closed system differ from an open one?
  6. How can energy be transfered?
  7. What are some types of waves?
  8. What is the electromagnetic spectrum?
  9. How can waves be described?
  10. What is the definition of work?
  11. How are newtons measured?
  12. Describe nuclear, geothermal, thermal, gravitational and elastic energies
  13. What are Contact Forces, Action-at-a-Distance Forces, Frictional Force, Gravitational Force, Tensional Force, Electrical Force, Normal Force, Magnetic Force, Air Resistance Force, Applied Force, and Spring Forces?

Link

http://www.glenbrook.k12.il.us/gbssci/Phys/Class/BBoard.html

http://www.mrfizzix.com/

http://www.phys.unsw.edu.au/~jw/FAQ.html

Wednesday, November 08, 2006

Homework 2

What is matter?
What are elements?
What is the structure of an atom?
What are the most common elements in the earth’s crust?
How is the periodic table organized?
What are metals?
Where are they located on the periodic table?
What are compounds?
What is a molecule?
What are mixtures?
What are some physical properties?
How do solids, liquids, and gases differ?
What is it called when matter changes from a gas to a liquid to a solid?
How do melting, freezing, sublimation, and condensation differ?
How can volume be described?
What is it called when atoms bond?
How does the state of matter and adding energy affect the movement of particles?
How does the state of matter and adding energy affect the distance of particles?
Describe how matter changes phases?
What are diffusion, active transport and osmosis?
How does the periodic table tell you about an element?


What is the nature of an atom?
How has atomic theory changed?Name three scientists and their contribution
What are subatomic particles?
What is the charge of electrons, protons, and neutrons?
What is an atomic mass unit?
What is an isotope?
How are isotopes represented?
What are some atomic models?
What is the wave mechanical or electron cloud model?
How do energy levels relate to electrons?
What happens when an electron gains energy?
How can elements be identified?
What are valence electrons?

Checklist of things to know
3.1a The modern model of the atom has evolved over a long period of time through thework of many scientists.
3.1b Each atom has a nucleus, with an overall positive charge, surrounded bynegatively charged electrons.
3.1c Subatomic particles contained in the nucleus include protons and neutrons.INDICATOR 3.1Chemistry 17
3.1d The proton is positively charged, and the neutron has no charge. The electron isnegatively charged.
3.1e Protons and electrons have equal but opposite charges. The number of protons equals the number of electrons in an atom