HW due Friday, July 19

2SDS pg. 204 #7-13

7. An alloy is a solid combination of atoms made up of two or more metals.

8. Two alloys I use regularly are Cutlery steel for utensils that I use to eat and Carat gold which is in a lot of the jewelry that I own.

9. Carbon is a nonmetal that is a part of both steel and stainless steel.

10. Chromium- platinum, also known as Cr3Pt, is a sturdy alloy that creates the basis of many razor blade edges.

11. Elements that act as semi-conductors are commonly known as metalloids. They lay in between metals and nonmetals, and they exemplify characteristics of both metals and nonmetals.

12. Three elements frequently used for doping semiconductors are phosphorus, arsenic, and gallium.

13. The primary use of the products of semi conductor technology is for letting computers process digital information; many semi-conductor devices have integrated circuits that are used in commuters and other electronic devices, as well. 

Bedtime Stories

Research by Yvonne Kelly of University College, London, proved that the ancient wisdom, in which parents urged their children to sleep routinely at an early time, is not entirely correct. While daughters benefit from regular bedtimes, Kelly has shown that sons do not. She began her observations by viewing the connections between sleep habits and mental abilities in teens and adults around the world. Her data exemplified that sleeping schedules went hand in hand with poor academic performance. However, it was surprising to discover that not a lot of people had researched sleep habits for children under the age of 18. Thus, she and a team of colleagues began a multidisciplinary research project called the Millennium Cohort Study; an examination of bedtimes and cognitive abilities of  11,178 children. This project occurred when the children were nine months, three years, five years and seven years old. Kelly and her colleagues tested whether the children were read to before sleeping, had televisions in their bedrooms, or had a regular, set bedtime. To test their IQ’s, the children were also asked, at the ages of three, five and seven, to take standardized reading, mathematical and spatial-awareness tests. Dr Kelly’s report, just published in the Journal of Epidemiology and Community Health, shows that by the time children had reached the age of seven, not having had a regular bedtime did seem to affect their reasoning, even when other relevant variables such as bedtime reading and televisions were controlled for. But that was true only if they were female. Also, on the IQ scale, whose mean value is 100 points, girls who had had regular bedtimes scored between eight and nine points more than those who did not; however, boys were not completely unaffected. Irregular bedtimes left their IQs about six points below those of their contemporaries at the age of three. But the distinction disappeared as they grew older. We found this article important because we never knew that there was sleep a difference between the sexes. Even Dr. Kelly did not expect it and she has no explanation to offer for it.

HW due Thursday, July 18

 2SDS pg. 204, #1-6

1. An allatrope is a different form of an element which contains very different physical and chemical properties.

2. Nitrogen, oxygen, sulfer, and lead.

3.
A. Diamonds are very expensive. A diamond is hardest substance known, does not conduct electricity, has a very high melting point, and is very difficult to find. Coal is flammable and very inexpensive. Lead inside of a pencil, which is made out of graphite, conducts electricity, is very, and inexpensive.
B. The properties of each of these differ because, even though they all come from the same element, they are allotropes of carbon, so they have different atomic arrangements.
C. he structure of carbon atoms in a diamond gives it its high melting point, hard shell, and rareness, which then causes it to be very expensive. The atomic makeup of graphite and coal causes them to be more common, reactive, and softer; thus, they cost less.

4. Engineered materials are materials made by scientists or engineers to improve natural materials by manufacturing methods that control the microstructure of materials. The makeup of natural materials is untouched and uncontrolled.

5. Ceramics are sturdy and have extremely high melting points. They are also strong at high temperatures; but, ceramics are brittle and when they are in high heat, or very cold, they crack.

6. Plastics can be customized to be either soft or hard, and it can also be made into optical fibers. Optical fibers replace copper wires, as well.

HW due Wednesday, July 17

2SCS #13-21 p. 181

13. 

A. 6 moles

B. 5 moles

C. 5 moles

14. 

A. 1 mole

B. 621 g

C. 28 g

D. 415 g

15.

14 + 16 + 16 = 46

32/46 = 70%, not 67%

16. 

A. Ag2S is 87% silver

B. Al2O3 is 53% aluminum

C. CaCO3 is 40% calcium

17. 

A. PbSO4 is 68% lead

B. 10% PbSO4 is in the ore sample

C. 6.8% Pb is in the total ore sample

D. 10% lead in the PbSO4 ore

18. 

A. Reusing is when a product is used again for the same purpose. For example: recycling means that a product is used again, or gray water is also an example of reusing.

B. 2 instances of recycling are creating compost piles and adding scraps of fruits and vegetables to make your soil nutrient. 2 examples of reusing are clothes and books.

19. 

A. 4 examples of renewable resources are solar energy, biomass, geothermal, and wind.

B. 4 examples of nonrenewable resources are coal, oil, natural gas, and uranium.

20.

A. Reusing

B. Recycling

C. Recycling

21. A light bulb would only be recyclable because once it dies out, you cannot use it again; however, a magazine would be recyclable and reusable.

Homework due Tuesday, July 16

1. The law of conservation of matter states that matter is neither created nor destroyed in a chemical reaction.

2. A scientific law summarizes what has been learned according to careful observation of nature.

3. Expressions such as "using up" and "throwing away" can be very misleading since one might think that matter is lost since you are getting rid of it; however, matter is neither created nor destroyed and atoms are forever there.

4.

a.

Reactants: Sn-1 H-1 F-1

Products: Sn-1 H-2 F-2

·      not balanced because the number of atoms per element on the reactant and products side is not the same, or balanced.

b.

 Reactants: Si-1 O-2 C-1

Products: Si-1 O-1 C-2

·      not balanced because the number of atoms per element on the reactant and products side is not the same, or balanced.

c.

Reactants: Al-1 O-3 H-6 Cl-3

Products: Al-1 O-3 H-6 Cl-3

·      balanced because the number of atoms per element on the reactant and products side is the same.

5.

a. The coefficient for H (g) is 3

b. The coefficient for NH3 gas is 2

c. The coefficient for N (g) is 1

6.

a. 1 WO3 + 3 H2 --> 1 W + 3 H2O

b. 2 PbS + 3 O2 --> 2 PbO + 2 SO2

c. 4 Fe + 3 O2 --> 2 Fe2O3

7. 

a. 1 Ca3(PO4)2 + 3 H2SO4 --> 2 H3PO4 + 3 CaSO4

b. 2 C8H18 + 25 O2 --> 16 CO2 + 18 H2O

8. 

a. Yes

Reactants: Na-2  S-1 O-4  K-2  Cl-1

Products: Na-2  S-1 O-4 K-2 Cl-1

b. No, because the subscripts remain the same, but the coefficients are altered to balance the equation. 

c. 1 Na2SO4 + 2 KCl --> 2 NaCl + 1 K2SO4

9. It would take 400,000 seconds to spend one mole of dollars.  (10 * 10^9)

10.

a. O2: 32 g

b. O3: 48 g

c. CaCO3: 100 g

d. Mg(OH)2: 58 g

e. C9H8O4: 180 g

HW due Monday, July 15

2SBS #9-22 pg. 151

9.

·      It is much more difficult to process and refine active metals as opposed to less active metals because metals that are more active combine with other elements which then form compounds; however, less active metals stay unconnected.

10.

·      Silver would most likely be the easiest to process since it does not react; thus, it does not combine with other elements or metals.

11.

·      Most elements exist in nature as minerals as opposed to pure metallic elements since they are more reactive.

12.

·      Reaction A is more likely to occur. This is due to the fact that chromium is less reactive than calcium.

13.

·      Reaction B is more likely to occur because zinc is more reactive than silver; thus, putting a reactive metal in a solution that is not reactive would trigger a reaction.

14. 

•                A. It wouldn’t be a good idea to stir a solution of lead nitrate with an iron spoon because the iron would cause a reaction since it is more reactive then lead.

•                B. Pb2(aq) + Fe(s) à Pb(s) + Fe2(aq)

15.

·      Oxidation means the loss of at least 1 electron that causes a metal to become a cation or an aqueous solution, and reduction is the gain or loss of electrons that causes a cation or aqueous solution to balance out; thus becoming a metal.

16. 

•                A. Au3+ + 3e à Au

•                B. V à V4+ + 4e-

•                C. Cu+ à Cu2+ + e-

17. 

•                A. reduction

•                B. oxidation

•                C. reduction

18. 

•                A. Zn was oxidized b/c 2 electrons were lost. It went from a solid to an aqueous solution/

•                B. Ni was reduced b/c 2 electrons were gained. It went from an aqueous solution to a solid/metal.

•                C. The reducing agent was Zn.

19. 

•                A. K+ was oxidized b/c it lost an electron. It became an aqueous solution.

•                B. Hg was reduced b/c it gained 2 electrons. It became a solid.

•                C. The oxidizing agent was Hg2+.

20. 

•                A. Al + Cr3  à Al3 + Cr

•                B. Mn2 + Mg à Mn + Mg2

21. 

•                A. Electrometallurgy uses an electrical current to decrease metal ions by supplying electrons.

•                B. Pyrometallurgy heats metals and ores to change metal cations to atoms.

•                C. Hydrometallurgy uses reactants in water solutions to take care of ores and other metal-containing substances.

22. 

•                A. Magnesiumà Electrometallurgy.

•                B. Leadà Pyrometallurgy.

A Fourth of July Unpleasant Surprise

This Fourth of July holiday, collectively Americans will eat some 150 million hot dogs, according to industry analysts. U.S. supermarkets alone sold more than $1.6 billion worth of hot dogs last year. That’s a lot of beef—and pork, and turkey, and chicken. Beef, pork, turkey, and chicken, surprsingly, are all components in making your average Fourth of July hotdog.  As of last year, hotdogs made by industry Oscar Mayer got knocked out of first place for most-consumed dogs by Sara Lee’s Ball Park brand; however nobody truly knows what goes inside these hotdogs.

Ball Park Hotdogs:
Turkey is produced by forcing bones, with attached edible tissue, through a sive or similar device under high pressure.

Pork is produced by using any "meat"  that can be taken off the bone by "advanced meat recovery (AMM) machinery" which separates the edible meat from the inedible without breaking the bone.

Water say that hot dogs must be less than 10 percent water under Ball Park Franks.

Corn syrup is often used to add texture and sweetness, but has many dangerous health risks when served at high amounts.

Each of these hot dogs contain about 20 percent (480 milligrams) of the recommended daily allotment of salt.

Potassium lactate is a common meat preservative because of its properties as an antimicrobial which means that it is capable of killing off harmful bacteria, but is not good for your liver.

Sodium phosphates is any of three sodium salt of phosphoric acids that can be used as a food preservative or to add texture.

Flavorings are a very repulsive idea. Most combinations of flavoring agents are okay to just be listed as "flavor" rather spelled out individually, so the packaging doesn’t have to tell you what the artificial flavor is really made up of.

Beef stock is usually made by boiling water with pieces of muscle, bones, joints, connective tissue and other parts of the carcass.

Sodium diacetat helps to fight fungus and bacterial growth and is often used as an artificial flavor for salt and vinegar chips; however, it is also what they use to make hand warmers warm.

Sodium erythorbate helps keep meat-based products pink, even when they really shouldn’t be or are not pink.. Some people report side effects, including dizziness, gastrointestinal issues, headaches and, if consumed in large quantities, kidney stones..

Sodium nitrate is a preservative that helps meats retain their color; unfortunately, animal studies have linked sodium nitrates to an increased risk of cancer. It’s also frequently found in fertilizers and fireworks!

Oscar Mayer Classics have a similar list of ingredients which consists of: mechanically separated turkey, mechanically separated chicken, pork, water, salt, ground mustard seed, sodium lactate, corn syrup, dextrose, sodium phosphates, sodium diacetate, sodium acorbate, sodium nitrate, and flavor. The two top companies, Oscar Mayer and Sara Lee Ball Park Brand now offer at least 34 hot dog varieties between them, ranging from Ball Park’s Cheese Franks to Oscar Mayer’s XXL Premium Beef Franks, all made with almost no real, healthy meat.

 http://www.scientificamerican.com/report.cfm?id=barbecue-food-science