Last updated 8-27-09*
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Building Block Series Quiz

1. In the picture we see that the man is made of lego building blocks. Later we will see that everything in the picture is made of building blocks. Those that make up the wood, glass, and cement are too small to see. If you were standing about a hundred yards from our lego man, could you see the lego building blocks? And might you mistake him as a real person?
2. On the right is a representation of a plastic called Low Density Polyethylene or LDPE for short. It is used to make squeeze bottles. The larger gray spheres are carbon atoms, and the white spheres are hydrogen atoms. What is the smallest repeating unit (building block) that would build these chains? (hint: It's 3 atoms)

#3. The equation E=mc2 can be used to calculate energy given off when mass is converted to energy or how much energy is required to create a certain amount of mass. Mass "m" is kilograms and "c" is speed of light in meters per second. A grain of sand weighs about one millionth of a kilogram (1/1,000,000). So the energy to make that much mas is:

E=    1 kg   x(300,000,000m/sec)2
   1,000,000

This answer will be in kg·m2·sec-2 (Remember sec-2 is the same as per sec2). These units (kg·m2·sec-2) have conveniently been given the name of joule, which is a common unit for energy. But we want this converted kilowatt hours because we know it costs $0.09 per kilowatt hour. A watt is defined as one joule per second. Below is a spreadsheet style setup of the dimensional analysis needed. Do the arithmetic to solve for the cost to make that much energy. Note that the "/sec" will go to the numerator and get canceled. Actually all units get canceled except dollars. Also note that all conversions have a numerator and denominator that are equal to each other.
Mass
velocity squared
conversion
conversion
conversion
conv
$/kilowatt_hour
1
kg
=300000000^2
m2·sec-2
joule
watt
1
hour
kilo
$0.09
=
$
1000000
kg·m2·sec-2
1 joule/sec
3600
sec
1000
kilowatt·hour

#4. Here is a guy who scares his neighbors with his Tesla coils. The sparks are streams of electrons flying off the left donut-shaped metal. Electrons (or electricity) don't usually jump into the air because air resists any electrons trying to move through it.

Look at the below illustration of the electromagnetic spectrum. Sparks and lightning produce light (electromagnetic radiation) across most of the spectrum. You have noticed how your radio or TV gets interference from lightning. That's because these produce radio and microwaves. What you don't see is the dangerous ultraviolet light and xrays that sparks create. Our friend here probably doesn't realize the amount of electromagnetic radiation he is exposing himself. I'd say the ultraviolet rays would be the most abundant light. 4a) Do a Web search and report on some dangers to health that ultraviolet light causes. 4b) The below chart has the wavelength of UV light around 10-8, but doesn't say what is the unit of measurement is. What is it?
#5. You learned that a proton, that is positively charged is attracted to an electron that is negatively charged. They pull on each other with equal force. Here's the formula for the attraction force between a proton and electron that are separated by the distance of the diameter of carbon atom (70 picometers).
F= k x q1 x q2
             r2
Force will be in newtons (force needed to accelerate a kilogram up to a speed of 1 meter per second and having only one second to do it.) "k" is constant that does the conversion. "q1" is the charge on the proton and "q2" is the charge on the electron. They are equal just opposite. "r2" is the distance (radius) between them squared. Charge is given in coulombs (C) named after a physicist. Below is a spreadsheet way of setting up the calculation.Remember the equal sign "=" causes the spreadsheet to do the calculaton of the scientific notation number. The only unit that doesn't cancel is N (newton). Note the "C-2" goes to the denominator. Do the calculations below to find the force. (For tips on calculating see below the table)
 
A
B
C
D
E
F
G
H
I
J
K
1   constant k that converts the units
charge on the
proton (q1)
charge on the
electron (q2)
r2=Distance "r" between proton & electron squared
conversion to get rid of pico squared
2 F=  
 =8.988*10^9
N·m2·C-2
=1.602*10^-19
C
=-1.602*10^-19
C    
pico
pico
3              
=70^2
 (picometers)2 =10^-12 =10^-12
You can copy these values into a spreadsheet. For example, =1.602*10^-19 can be copied to a cell in a spreadsheet and it will respond with 1.602E-19 where the "E-19" means 10 with the Exponent of -19. That's what calculators do also. If I were doing these calculations on a calculator, I would ignore the powers of 10. So I would multiply 8.988 x 1.602x1.602 then divide by 70 twice (which is the same dividing by 702). I'd would write that answer down. I would move both of the "10^-12" to the numerator and then make them positive. So that's 10^12 twice. I would add up all the exponents from the 10's. So that is +9 + -19 + -19 + 12 + 12. That adds up to "-5." So my calculator answer is followed by x10-5. I would then move the decimal place left or right to get the standard scientific notation where you begin with 1 digit followed by decimal point and the decimal fractions. I would adjust the x10-5 to compensate for how much I moved the decimal place.

6. From the salad, you are acquainted with the building blocks for the elements at a personal level. Match the atomic particle to the correct sense.

1. Protons

2. Electrons

3. Neutrons.

Senses: Sight, Taste, Pressure (from weight)
7. A fundamental law about charges is demonstrated in this static electricity picture. Electrons move up to the girls hair and then the hair separates. What can you say about the force that electrons have on other electrons?
static electricity girl with hair standing up
8. In the picture of the helium atom to the right, we see the electrons staying away from each other, but the protons (+) seem to disobey the rule about like charges repelling. How is it that protons will sit up against each other in the nucleus of an atom? (Also, mention the name of the force that overcomes the electrical repulsion force)
9. Ionic bonding occurs when two charged atoms (ions) have opposite charges. Which two atoms to the right will be attracted to each other? (hint: count protons and electrons)
10. In the movie, "Total Recall", the alien factory could decompose ice in the Martian soil into oxygen and hydrogen. That would require very high temperatures and would end up with a flammable mixture of oxygen & hydrogen. A better idea is use the iron oxide that is in Martian soil. That would turn into iron metal and oxygen gas at a temperature much lower than decomposing water.
10a) What temperature (in Celsius) is necessary to decompose red iron(III) oxide (Fe2O3) which will liberate oxygen? (hint: Do a Google search for: iron oxide melting point. A Wikipedia article should come up. Check it out).
10b) Write the balanced decomposition equation.

11a) What are the three most abundant elements in the Earth's crust?

11b) In the picture snow is on the Earth's crust, so what additional element besides the three mentioned in "11a" is sure to be present?
12. What element is in all organic compounds?
13. Hydrocarbons are the simplest of all organic compounds, but which hydrocarbon is the simplest?

14. Building blocks have to connect to other blocks. In the picture we see oxygen, hydrogen, and carbon. Looking at the number of outer electrons each have and the number of vacancies each have...
A) ...what is the maximum of atoms hydrogen can connect to? ...oxygen can connect to? and carbon can connect to?

B) Which element is the most versatile then?
15. To the right are some of the smaller organic acids, with formic acid being the smallest. The small yellow arrows indicate the hydrogen which has a tendency to come off as a proton. Many birds hunt for formic acid. 15a) Do a Web search for bird anting and report what that is and why birds like formic acid.
15b) Some remedies for ant bites use a base to neutralize the formic acid. Baking soda (sodium hydrogen carbonate/NaHCO3) is one of them. What is the missing (???) compound in the below equation for formic acid reacting with baking soda?
HCOOH + NaHCO3 --> HCOONa + H2O + ???
16. Creating flavors is a big industry and two of our organic compounds (alcohols and organic acids) are common ingredients. Here we see how ethanol (drinking alcohol) and butyric acid combine to make a pineapple flavor. I like the aroma of pineapple and that of ethanol. But what does butyric acid smell like?
17. We often hear consumers complain about artificial flavors, but most products still have them. Visit the below link and read enough to come up with three reasons why artificial flavors are so common despite the complaints.
http://www.uefap.com/reading/exercise/kavaler/kavaler6.htm
18. Collagen is a great example of building blocks. With just three amino acids that repeat, it forms long twisted strands (a triple helix). About one quarter of all of the protein in your body is collagen.
18a) What parts of the body use collagen?
18b) As these 3 amino acids connect, the circled atoms will come off as H2O (Note: on glycine just one of those circled hydrogen atoms come off). What is the molar mass (molecular weight) of the tripeptide that is formed when these 3 amino acids come together?
19. To the right is a summary of what elements are needed to make each category of organic compounds. There is just one error. RNA and DNA only need five of the six elements. Which element is not needed?
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