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I need help. 12 questions, Chemistry/Physical Science.

Ok, I'm new here to the site. My fiance is a junior in college. She has missed some classes due to health related problems. Anyhow, she has had a lot of coursework and now finals pile up on her. She needs some help. I've been out of school for almost 3 years now, had to drop out of college to work, and I am a bit rusty and am not of much use. So, I am down to my last options, asking for help online. I am willing to paypal anyone $30 on Friday if they can answer these 12 questions 80% correctly.

The downside, I have less than 3 hours to get these answered. I need them by midnight tonight my time, it is currently 9:18.


Without further ado, the questions -



Short Answer: Answer the following questions. (Round to two decimal places unless otherwise directed)

1. Determine whether the following would have the same density and give a reason for your answer. (a) a one cubic centimeter sample of lead as opposed to a one cubic centimeter sample of iron. (b) a one cubic centimeter sample of liquid water as opposed to a one cubic centimeter sample of ice. (c) a one cubic centimeter sample of dry air as opposed to a one cubic centimeter sample of humid air. (d) a one centimeter sampe of hot water as opposed to a one centimeter sample of cold water. (e) a one centimeter sample of styrofoam peanuts or the the same styrofoam peanuts crushed.



2. Give an example of each of the following if possible describing why they are examples: a) constant velocity and constant speed, b) varying velocity and constant speed, c) constant velocity and varying speed, and d) varying velocity and varying speed.



3. What purpose does a walking stick serve when you are hiking in rough country? Be specific.



4. How much heat is required to melt 50 g of mercury at -45 degrees Celsius to 425 degrees Celsius. Describe the whole process from the molecular level. (melting point = -38.9 degrees Celsius, boiling point = 356.58 degrees Celsius, specific heat = 0.03325 cal/g-degree C, heat of fusion = 2.7 cal/g, heat of vaporization = 65 cal/g)



5. Why is it not a good idea for a large band to march in unison across a bridge?



6. Suppose you have a 600 ?, an 800 ?, and a 1.30 k? resistor. What is (a) the maximum, and (b) the minimum resistance you can obtain by combining these?



7. Why do astronauts in orbit around Earth see a black sky with stars that do not twinkle but see a blue Earth?



8. An element has 33 protons in its nucleus. (a) What is its atomic number?, (b) What is its name?, (c) What is its electron configuration?, (d) How many electrons and neutrons are present in its most common isotope?



9. (a) How can you show that a chemical reaction adhers to the law of conservation of mass? (b) Write and balance the chemical reaction: magnesium hydroxide added to phosphoric acid produces magnesium phosphate and water, (c) What type of reaction is this?, (d) Determine the mass percentage of the elements in each compound of the reactants and products, and (e) Determine the total mass of reactants and compare this number to the total mass of products. Explain what this tells you about the reaction.



10. For each of the following reatants, list the proton acceptor, proton donor, acid, and base: (a) H?SO??aq? + H?O?l? ? H?O??aq? + SO?²??aq? (b) C?H?NH??l? + H?O?l? ? C?H?NH???aq? + OH??aq? (c) H?PO??aq? + HC?H?O??aq? ? H?C?H?O???aq? + PO???aq? (d) H?O?l? + H?O?l? ? H?O??aq? + OH??aq?



11. (a) What does the octane number of gasoline describe?, (b) On what is the number based?, (c) Would low or high octane ratings give the best results in your car's engine?, (d) Why?



12. (a) Describe the three types of radioactive decay according to type of particle if any is emitted, most penetrating, fastest in regards to velocity, and how it can be stopped. (b) Tell whether the following isotopes would be radioactive and why: (i) carbon-13, (ii) iodine-128, (iii) fluorine-19, (iv) americium-244, (v) silicon-28

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