1. This summer was a great success. I think it is mostly because of the concept of "students teaching students."I think this worked because classmates put concepts in their words which helps me.
2. The suggestions I have for tweaking or changing the course are having less lab reports because as much as much as they help enforce a concept, it doesn't really help when we don't understand what we need to do for the lab, which adds confusion to the concept.
3. Another way to enforce science understanding and presentations may be to assign a night where we watch some documentary on Tv and right like a couple of sentences to what we learned and it's significance. Since everyone loves watching Tv, it would be a good way to learn about a concept by doing something we enjoy.
4. I think the blogs are good the way they are. They keep all of our work neat by having different tabs, and its always accessible.
5.Yes, the instructor should check homework on the blogs because it forces the students to actually read the homework assignment, which will help us do better on quizzes and tests.
6. A more creative way to enforce Chemistry consists of doing more projects than tests. This is because some students may be bad test takers, which is a disadvantage to these students. However, I think that tests force us to study and understand what we are learning.
Thursday, July 25, 2013
Wednesday, July 24, 2013
3SCS (p.279) #1,3,6,13 and 3SBS (p.258) #11,12
7/24/13
3SCS (p.279) #1,3,6,13
1. a. Monomer: 1repeating unit
b. Dimer: 2 repeating units
c. Trimer: 3 repeating units
d. Polymer: unlimited
3. Natural polymers: medicines, food additives, cotton, and silk
Synthetic polymers: paint components, fabrics, rubber, and foams
6. The term unsaturated is used to describe the structures of alkenes and alkynes because not all carbon atoms are bonded to their full capacity with four other atoms. And alkenes contain carbon-carbon double bonds.
13.
3SBS (p.258) #11,12
11. a. riding a bike: i
b. illuminating a lightbulb: iii
c. producing electricity in a wind-powered generator: i
d. running a gasoline-powered lawn mower: ii
12. The other 75% of the energy is lost to the surrounding as thermal energy, heat.
3SCS (p.279) #1,3,6,13
1. a. Monomer: 1repeating unit
b. Dimer: 2 repeating units
c. Trimer: 3 repeating units
d. Polymer: unlimited
3. Natural polymers: medicines, food additives, cotton, and silk
Synthetic polymers: paint components, fabrics, rubber, and foams
6. The term unsaturated is used to describe the structures of alkenes and alkynes because not all carbon atoms are bonded to their full capacity with four other atoms. And alkenes contain carbon-carbon double bonds.
13.
3SBS (p.258) #11,12
11. a. riding a bike: i
b. illuminating a lightbulb: iii
c. producing electricity in a wind-powered generator: i
d. running a gasoline-powered lawn mower: ii
12. The other 75% of the energy is lost to the surrounding as thermal energy, heat.
Tuesday, July 23, 2013
Blog Question
Fossil fuels vs. alternative energy. How do hybrid vehicles help our planet? Electric vehicles?
Fossil fuels are our primary energy supply and consist of coil, oil, and natural gases. Fossil fuels are also nonrenewable. Therefore, we need alternative energy, which is energy produced from sources other than fossil fuels. Hybrids help our planet because they consist of both gasoline burning engines as well as a battery-powered electric motor. The batteries are recharged while driving, through conversion of the car's kinetic energy into stored chemical potential energy. They are also helpful because they switch from gasoline engines to electric motors. Electric vehicles reduced the amount of waste that is being produced from the burning of gas and the release of oil.
Fossil fuels are our primary energy supply and consist of coil, oil, and natural gases. Fossil fuels are also nonrenewable. Therefore, we need alternative energy, which is energy produced from sources other than fossil fuels. Hybrids help our planet because they consist of both gasoline burning engines as well as a battery-powered electric motor. The batteries are recharged while driving, through conversion of the car's kinetic energy into stored chemical potential energy. They are also helpful because they switch from gasoline engines to electric motors. Electric vehicles reduced the amount of waste that is being produced from the burning of gas and the release of oil.
3SAS (p.235) #31-38 and 3SBS (p.258) #1-10
7/23/13
3SAS (p.235) #31-38
31. a. name: Propane; molecular formula: C3H8
b. name: Pentane; molecular formula: C5H12
32. The suffix -ane in the carbon-carbon bonding in hexane implies that hexane is an alkane.
33. Yes, each of the three molecules are isomers of one another because they all have identical molecular formulas, but just a different arrangement of atoms.
34.
35. Butane is the shortest-chain alkane that demonstrates isomerism because it is and alkane with four or more carbon atoms that can be demonstrated as straight-chain structures, branched-chain structures, or ring structures.
36. Both representations are correct because it doesn't change the molecular formula, they are just demonstrated in different ways; therefore they are structural isomers.
37. a. Two hexane structural isomers, one straight chained, and the other branched-chained:
b. Of the two isomers, the straight-chain would have the lowest boiling point because it has a weaker intermolecular force. Where as the branch-chain molecule has a greater intermolecular force, resulting in a higher boiling point.
38. a. A short-straight chain would have the lowest boiling point because of the weaker intermolecular forces. And because of this the bonds are much easier to break apart.
b. A short-branched chain would have the lowest boiling point because longer branched-chains have a stronger molecular force.
c. A long, straight chain has a lower boiling point because it has a weaker intermolecular force than a short, branched-chain.
3SBS (p.258) #1-10
1. Petroleum is sometimes considered "buried sunshine" because as a fossil fuel, it originates from biomolecules of prehistoric plants and animals, and as sunlight is captured by these prehistoric gren plants during photosynthesis, the energy released is the burning of petroleum.
2. a. Potential energy is energy of position, or stored energy ready to be released. An example is the energy within an unreleased winded up spring toy.
b. Kinetic energy is energy related to motion. An example is a car rolling down a hill.
3. During a chemical reaction is an energy-releasing reaction that takes place, the bonds break and reactant atoms reorganize to form new bonds and release energy. If more energy is released than originally started with, the reaction is exothermic, but if less energy is released than originally started with, the reaction is endothermic.
4. A molecule of butane has more potential energy because it has more carbon atoms and a higher boiling point than methane. Additionally, the bonds of butane are harder to break apart, resulting in a higher potential energy.
5. a. Potential energy
b. Potential energy
c. Kinetic energy
d. Potential energy
e. Kinetic energy
6. Energy is required to break chemical bonds because energy causes reactant bonds to break and eventually reorganize to form new product bonds and energy.
7. a. Burning wood in a campfire: exothermic because more energy (heat) is released than is required to begin the chemical reaction.
b. Cracking large hydrocarbon molecules: endothermic because the molecule is being broken up; therefore, energy is being used.
c. Digesting a candy bar: endothermic because the molecule is being broken up; therefore energy is being used.
8. Burning a candle is an exothermic reaction because the energy released in the product is greater than the energy used in the reactant to break the bond. Basically more energy is given off than is added, making it exothermic.
9.
10. The law of conservation of energy states that energy is neither created nor destroyed in any mechanical, physical, or chemical process.
3SAS (p.235) #31-38
31. a. name: Propane; molecular formula: C3H8
b. name: Pentane; molecular formula: C5H12
32. The suffix -ane in the carbon-carbon bonding in hexane implies that hexane is an alkane.
33. Yes, each of the three molecules are isomers of one another because they all have identical molecular formulas, but just a different arrangement of atoms.
34.
35. Butane is the shortest-chain alkane that demonstrates isomerism because it is and alkane with four or more carbon atoms that can be demonstrated as straight-chain structures, branched-chain structures, or ring structures.
36. Both representations are correct because it doesn't change the molecular formula, they are just demonstrated in different ways; therefore they are structural isomers.
37. a. Two hexane structural isomers, one straight chained, and the other branched-chained:
b. Of the two isomers, the straight-chain would have the lowest boiling point because it has a weaker intermolecular force. Where as the branch-chain molecule has a greater intermolecular force, resulting in a higher boiling point.
38. a. A short-straight chain would have the lowest boiling point because of the weaker intermolecular forces. And because of this the bonds are much easier to break apart.
b. A short-branched chain would have the lowest boiling point because longer branched-chains have a stronger molecular force.
c. A long, straight chain has a lower boiling point because it has a weaker intermolecular force than a short, branched-chain.
3SBS (p.258) #1-10
1. Petroleum is sometimes considered "buried sunshine" because as a fossil fuel, it originates from biomolecules of prehistoric plants and animals, and as sunlight is captured by these prehistoric gren plants during photosynthesis, the energy released is the burning of petroleum.
2. a. Potential energy is energy of position, or stored energy ready to be released. An example is the energy within an unreleased winded up spring toy.
b. Kinetic energy is energy related to motion. An example is a car rolling down a hill.
3. During a chemical reaction is an energy-releasing reaction that takes place, the bonds break and reactant atoms reorganize to form new bonds and release energy. If more energy is released than originally started with, the reaction is exothermic, but if less energy is released than originally started with, the reaction is endothermic.
4. A molecule of butane has more potential energy because it has more carbon atoms and a higher boiling point than methane. Additionally, the bonds of butane are harder to break apart, resulting in a higher potential energy.
5. a. Potential energy
b. Potential energy
c. Kinetic energy
d. Potential energy
e. Kinetic energy
6. Energy is required to break chemical bonds because energy causes reactant bonds to break and eventually reorganize to form new product bonds and energy.
7. a. Burning wood in a campfire: exothermic because more energy (heat) is released than is required to begin the chemical reaction.
b. Cracking large hydrocarbon molecules: endothermic because the molecule is being broken up; therefore, energy is being used.
c. Digesting a candy bar: endothermic because the molecule is being broken up; therefore energy is being used.
8. Burning a candle is an exothermic reaction because the energy released in the product is greater than the energy used in the reactant to break the bond. Basically more energy is given off than is added, making it exothermic.
9.
10. The law of conservation of energy states that energy is neither created nor destroyed in any mechanical, physical, or chemical process.
Monday, July 22, 2013
Blog Question
Blog about distillation to separate alcohol and water.
To separate alcohol and water we use the distillation process. Since water has a high boiling point and alcohol has a low boiling point, when the mixture is heated the alcohol will vaporize first and leave the distillation flask. The alcohol, now, will then condense back into a liquid and can then be collected separately. This all happens before water begins to boil. Then the same process will occur for the water.
To separate alcohol and water we use the distillation process. Since water has a high boiling point and alcohol has a low boiling point, when the mixture is heated the alcohol will vaporize first and leave the distillation flask. The alcohol, now, will then condense back into a liquid and can then be collected separately. This all happens before water begins to boil. Then the same process will occur for the water.
Unit 4 B.3 (p.344) #1-4; Unit 4 B.8 (p.350) #1-6, and Unit 3 SAS (p.233) #1-30 (except #: 2,4,9,14,24,25)
7/22/13
Unit 4 B.3 (p.344) #1-4
1. Human exposure to ultraviolet radiation is potentially more harmful than exposure to infrared radiation because too much exposure to ultraviolet radiation can cause a sunburn, which can lead to skin cancer.
2. Two essential roles played by visible solar radiation is one they can energize electrons in some chemical bonds, which, two, provides energy needed for photosynthesis reactions.
3. Dry, arid regions in the United States experience wider air-temperature fluctuations from night to day then do more humid states because there is less water vapor; therefore infrared radiation isn't stored, reradiated, or reflected back into the atmosphere from electromagnetic radiation that is transformed in the clouds to produce infrared radiation. However, heat does reach the earth.
4. a. Day time temperatures would be affected if Earth had less dense atmosphere because it would be colder. This is because with less greenhouse gasses, like CO2 or H2O, less infrared radiation would be absorbed and be reflected back onto the atmosphere from the UV and visible radiation that was transformed to IR radiation in the clouds. In all less heat energy would be formed from less absorbed infrared radiation.
b. The night time temperatures would be affected if Earth has less dense atmosphere because it would be colder than it would normally be because one there is no presence of the sun and two because less infrared radiation is absorbed and reflected back onto Earth, making it colder.
Unit 4 B.8 (p.350) #1-6
1. 1kg of carbon dioxide is produced daily by all 10 Riverwood High School buses.
2. 0.40 L of fuel are consumed daily by buses idling at Riverwood High School.
3. In a 180-day school year, 180g of carbon dioxide would be released into the atmosphere by these buses, and 72L of fuel would be consumed.
4. Atmospheric CO2 levels have increased by about 30% since 1800 because of the clearing of forests, combustion of cutting and scrap timbers, and because of the burning of fossil fuels.
5. Yes, I do think the school bus idling policy will significantly affect annual worldwide supply of fossil fuels that are converted to carbon dioxide because as years go by, more fossil fuels will be needed for more buses.
6. The school buss idling policy is necessary to help preserve the burning of fossil fuels. And hopefully with this policy it will help when years go by and more fossil fuels will be needed.
Unit 3 SAS (p.233) #1-30 (except: 2,4,9,14,24,25)
1. Hydrocarbons are molecular compounds that only contain atoms of hydrogen and carbon.
3. The characteristic of petroleum that make it a valuable resource is that it is used as fuel in many U.S. automobiles, petroleum-based fuels provide heat to homes, generates electricity, and is useful to produce everyday products.
5. By saying oil is crude what is meant is that it is pumped from under grown and cannot be commercially used in its natural state, it must go through refinement where it is separated into simpler mixtures.
6. a. The average number of barrels of petroleum used daily int he United States for building purposes is: 0.11 x 20,000,000 = 2,200,000 barrels
b. The amount of barrels of petroleum burned as fuel daily in the United States is:
0.89 x 20,000,000 = 17,800,000 barrels
7. Fuels obtained from crude petroleum include heating and cooking fuel, petrol jelly, asphalt, petroleum coke, and many oils refined oils, gas oil, road oils, and more.
8. a. Four household items made from petroleum: clothing, carpeting, sports equipment, and plastic bottles.
b. Clothing could be made out of cotton, carpeting could also be made out of cotton, sports equipment can be made out of rubber like rubber balls, and plastic bottles could be made out of aluminum.
10. a. The world region that has the most petroleum reserves relative to its population is Eastern Europe.
b. The region that has the least petroleum reserves relative to its population is Central Asia.
11. a. The regions that consume a greater proportion of the world's supply of petroleum than they possess are North America, Central Asia, Far East, and Oceania, Western and Eastern Europe.
b. The regions that consume a smaller proportion of the world's supply of petroleum than they posses are Middle East, Africa, Central and South America.
12. Density could be used to separate two different liquids under the conditions that a substance is insoluble in each other.
13. A mixture of water and acetone would be the easiest to separate from each other since water has the highest boiling point and acetone has the lowest boiling point of the four substances listed; therefore, they would separate easily by distillation.
15.
16. Fractional distillation does not separate each substance in crude oil, instead it produces many different mixtures called fractions. Fractional distillation is a continuous process that consists of a distillation column and various temperatures in order to separate solutions. Simple distillation only involves a apparatus and separates a solution using evaporation and condensation.
17. Three useful products that derived from petroleum's fractions:
- light: motor gasoline and refined oil
-intermediate: gas oil and heavy furnace oil
-heavy: lubricating oil/grease and heavy oils/wax
18. In a distillation tower, I would expect the fraction with the highest boiling point to be removed at the bottom of the tower because it is hotter at the bottom, which is needed to separate the bonds between molecules. And there are thick liquids that never vaporize
19. After fractional distillation, a way to further separate the mixtures is distillation.
20. In the order from highest to lowest according to their boiling points are methane, pentane, hexane, octane. The higher the boiling point is, the stronger the intermolecular forces.
21. A covalent bond is the sharing of two or more valence electrons between two atoms, allowing both atoms to completely fill out their outer shells.
22. Atoms with filled outer electron shells do not form covalent bonds because they are usually stable; therefore, they are chemically unreactive.
23. The analogy that two dogs are tugging on the same sock describe the way that shared electrons hold together atoms in a covalent bond because the two dogs pulling away from each other are still connected by the need to want the sock; therefore, sharing the sock that connects them together.
26. a. The information that a structural formula conveys but a molecular formula does not is the make up of a molecule, as well as how high the boiling point is.
b. A structural formula is an inadequate representation of an actual molecule because it shows how strong molecular bonds within the formula is, as well as the boiling point of the formula
27. a. Lewis dot structure
b. Structural formula
28. The electron dot representation of carbon atom only shows four dots and not six because two electrons are located in the inner shell of an atom, and the four electrons are located in the outer shell.
29. a. C9H20
b. C16H34
c. C10H22
d. C18H38
30. a. 128g
b. 226g
c. 142g
d. 254g
Unit 4 B.3 (p.344) #1-4
1. Human exposure to ultraviolet radiation is potentially more harmful than exposure to infrared radiation because too much exposure to ultraviolet radiation can cause a sunburn, which can lead to skin cancer.
2. Two essential roles played by visible solar radiation is one they can energize electrons in some chemical bonds, which, two, provides energy needed for photosynthesis reactions.
3. Dry, arid regions in the United States experience wider air-temperature fluctuations from night to day then do more humid states because there is less water vapor; therefore infrared radiation isn't stored, reradiated, or reflected back into the atmosphere from electromagnetic radiation that is transformed in the clouds to produce infrared radiation. However, heat does reach the earth.
4. a. Day time temperatures would be affected if Earth had less dense atmosphere because it would be colder. This is because with less greenhouse gasses, like CO2 or H2O, less infrared radiation would be absorbed and be reflected back onto the atmosphere from the UV and visible radiation that was transformed to IR radiation in the clouds. In all less heat energy would be formed from less absorbed infrared radiation.
b. The night time temperatures would be affected if Earth has less dense atmosphere because it would be colder than it would normally be because one there is no presence of the sun and two because less infrared radiation is absorbed and reflected back onto Earth, making it colder.
Unit 4 B.8 (p.350) #1-6
1. 1kg of carbon dioxide is produced daily by all 10 Riverwood High School buses.
2. 0.40 L of fuel are consumed daily by buses idling at Riverwood High School.
3. In a 180-day school year, 180g of carbon dioxide would be released into the atmosphere by these buses, and 72L of fuel would be consumed.
4. Atmospheric CO2 levels have increased by about 30% since 1800 because of the clearing of forests, combustion of cutting and scrap timbers, and because of the burning of fossil fuels.
5. Yes, I do think the school bus idling policy will significantly affect annual worldwide supply of fossil fuels that are converted to carbon dioxide because as years go by, more fossil fuels will be needed for more buses.
6. The school buss idling policy is necessary to help preserve the burning of fossil fuels. And hopefully with this policy it will help when years go by and more fossil fuels will be needed.
Unit 3 SAS (p.233) #1-30 (except: 2,4,9,14,24,25)
1. Hydrocarbons are molecular compounds that only contain atoms of hydrogen and carbon.
3. The characteristic of petroleum that make it a valuable resource is that it is used as fuel in many U.S. automobiles, petroleum-based fuels provide heat to homes, generates electricity, and is useful to produce everyday products.
5. By saying oil is crude what is meant is that it is pumped from under grown and cannot be commercially used in its natural state, it must go through refinement where it is separated into simpler mixtures.
6. a. The average number of barrels of petroleum used daily int he United States for building purposes is: 0.11 x 20,000,000 = 2,200,000 barrels
b. The amount of barrels of petroleum burned as fuel daily in the United States is:
0.89 x 20,000,000 = 17,800,000 barrels
7. Fuels obtained from crude petroleum include heating and cooking fuel, petrol jelly, asphalt, petroleum coke, and many oils refined oils, gas oil, road oils, and more.
8. a. Four household items made from petroleum: clothing, carpeting, sports equipment, and plastic bottles.
b. Clothing could be made out of cotton, carpeting could also be made out of cotton, sports equipment can be made out of rubber like rubber balls, and plastic bottles could be made out of aluminum.
10. a. The world region that has the most petroleum reserves relative to its population is Eastern Europe.
b. The region that has the least petroleum reserves relative to its population is Central Asia.
11. a. The regions that consume a greater proportion of the world's supply of petroleum than they possess are North America, Central Asia, Far East, and Oceania, Western and Eastern Europe.
b. The regions that consume a smaller proportion of the world's supply of petroleum than they posses are Middle East, Africa, Central and South America.
12. Density could be used to separate two different liquids under the conditions that a substance is insoluble in each other.
13. A mixture of water and acetone would be the easiest to separate from each other since water has the highest boiling point and acetone has the lowest boiling point of the four substances listed; therefore, they would separate easily by distillation.
15.
16. Fractional distillation does not separate each substance in crude oil, instead it produces many different mixtures called fractions. Fractional distillation is a continuous process that consists of a distillation column and various temperatures in order to separate solutions. Simple distillation only involves a apparatus and separates a solution using evaporation and condensation.
17. Three useful products that derived from petroleum's fractions:
- light: motor gasoline and refined oil
-intermediate: gas oil and heavy furnace oil
-heavy: lubricating oil/grease and heavy oils/wax
18. In a distillation tower, I would expect the fraction with the highest boiling point to be removed at the bottom of the tower because it is hotter at the bottom, which is needed to separate the bonds between molecules. And there are thick liquids that never vaporize
19. After fractional distillation, a way to further separate the mixtures is distillation.
20. In the order from highest to lowest according to their boiling points are methane, pentane, hexane, octane. The higher the boiling point is, the stronger the intermolecular forces.
21. A covalent bond is the sharing of two or more valence electrons between two atoms, allowing both atoms to completely fill out their outer shells.
22. Atoms with filled outer electron shells do not form covalent bonds because they are usually stable; therefore, they are chemically unreactive.
23. The analogy that two dogs are tugging on the same sock describe the way that shared electrons hold together atoms in a covalent bond because the two dogs pulling away from each other are still connected by the need to want the sock; therefore, sharing the sock that connects them together.
26. a. The information that a structural formula conveys but a molecular formula does not is the make up of a molecule, as well as how high the boiling point is.
b. A structural formula is an inadequate representation of an actual molecule because it shows how strong molecular bonds within the formula is, as well as the boiling point of the formula
27. a. Lewis dot structure
b. Structural formula
28. The electron dot representation of carbon atom only shows four dots and not six because two electrons are located in the inner shell of an atom, and the four electrons are located in the outer shell.
29. a. C9H20
b. C16H34
c. C10H22
d. C18H38
30. a. 128g
b. 226g
c. 142g
d. 254g
Lab Report: Striking it Rich
LAB REPORT:
Striking it Rich
7/22/13
Charlie, Georgie, Ben
Dr. Forman
Lab Questions:
1. b. Yes, the treated coins appear to be composed of metals other than copper because it turned silver. This silver proves that there is the appearance of zinc in the penny as well.
2. I would decide the claim (that precious metals was produced from this investigation) would be incorrect. Because pennies are composed of zinc and copper These two metals could not react to make a precious metal, but instead they will combine together to form an alloy.
3. Two practical uses for metallic changes similar to those we observed in this investigation is that because alloys were formed, this caused a stronger metal to be formed from less strong elements that composed them. These alloys can then be used for everyday uses.
4. a. The penny that was only placed in the bubbling zinc chloride solution formed a less combined alloy of copper and zinc. However, the penny that was placed both in the bubbling zinc chloride solution and directly placed on the hot plate was formed a more combined alloy of copper and zinc. In all, the atoms formed different reactions depending on the procedure they endured.
b. Yes, the treated pennies could be converted back to its original coin by adding hydrochloric acid to the treated pennies.
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