The Chemicals in Your Life
Chem 3070 Exam I March 1, 1995
Dr. Stone

There are 40 multiple choice questions (80 points) and 1 essay question (20 points). You will have 60 minutes to complete the exam. You may use the periodic chart inside your book cover, and you may use a 3x5 card with anything you want written on it.

1. Which science is primarily concerned with the study of matter and the changes it undergoes?
a. biology b. chemistry c. geology d. physics

2. One way of rating complexity in scientific disciplines is with respect to the number of variables in the experiments. Which of the following scientific disciplines would have experiments that are the most complex with regard to the number of variables.
a. chemistry b. physics c. biology d. human psychology

3. Both mass and weight provide a measure of the amount of matter. Mass is
a. independent of location b. dependant of location c. easier to measure d. measured only with the metric system

4. On Mars gravity is 1/3 of that on Earth. What would the weight on Mars be if the person weighed 150 lbs on Earth?
a. 50 lbs b. 100 lbs. c. 150 lbs d. 200 lbs

5. Which of the following is an example of a physical change?
a. ice melting b. bread rising c. gasoline burning d. plant growth

6. Which of the following is an example of a chemical change?
a. ice melting b. body using sugar for energy
c. water evaporating from grapes d. cutting hair

7. The label on a jar of peanut butter lists peanuts, salt, water, and preservatives. From this information, peanut butter is a
a. mixture b. pure substance c. element d. compound

8. Which of the following cannot be a symbol for an element?
a. Co b. CO c. F d. Cl

9. What is the chemical symbol for Potassium?
a. P b. Po c. Pt d. K

10. How many centimeters are in 5 meters?
a. 50 b. 0.5 c. 500 d. 100

11. After a particularly grueling day studying for your chemistry exam, you reach for the aspirin bottle to get some relief for your headache. The aspirin tablets contain 325 mg of active stuff. How many grams is this?
a. 32.5 b. 0.325 c. 3.25 d. 54.3

12. Which of the following symbols represents the compound, sucrose:
a. S b. C12H24O11 c. Sc d. Sr

13. The element that Marie Curie discovered and named after her native land was:
a. Po b. Pb c. Pm d. Pu

14. The freezing point of water on the Celsius scale is:
a. 32 b. -32 c. 0 d. 100

15. Arrange the following prefixes in the order of increasing size:
a. mega, kilo, centi, milli, micro
b. micro, milli, centi, kilo, mega
c. milli, centi, kilo, mega, micro
d. micro, centi, kilo, milli, mega

16. The density of water is 1.00 g/ml, what is the mass of 1 liter of water?
a. 1 kg b. 2.2 kg c. 1 lb d. 100 g

17. Sea water is approximately 9% Sodium chloride (NaCl), that means that there are 9 grams of NaCl in every 100 ml of water. Using this information, calculate the density of sea water.
a. 0.09 g/ml b. 0.9 g/ml c. 9 g/ml d. none of these

18. Which of the following substances is homogeneous?
a. wood b. seltzer water in a glass with bubbles
c. a carrot d. none of the above

19. The Greek word 'atomos' means:
a. indivisible b. atom c. invisible d. continuous

20. Hydrogen peroxide decomposes into water and oxygen when exposed to heat or light or some chemicals. A tightly capped bottle of hydrogen peroxide is placed on a mass scale (as balance) and exposed to light for three weeks. The mass reading on the scale does not change. This is an example of:
a. the Law of Conservation of Mass b. the Law of Definite Proportions
c. the Law of Constant Composition d. the Law of Multiple Proportions

21. When 10.00 g of lead and 1.56 g of sulfur react, 11.56 g of lead sulfide is produced. Suppose 30.00 g of lead and 1.56 g of sulfur are allowed to react. Analysis of the reaction mixture would show:
a. 31.56 g of lead sulfide b. 34.68 g of lead sulfide
c. 11.56 g of lead sulfide and 20.00 g of lead d. none of the above

22. Which of the following does not occur during a chemical reaction:
a. matter is rearranged b. matter is conserved
c. matter is destroyed d. atoms react with other atoms

23. The ability to recycle materials such as glass, aluminum or plastic is an illustration of:
a. the Law of Conservation of Mass b. the Law of Definite Proportions
c. the ingenuity of chemists d. lots of media hype

24. An anion is:
a. a negatively charged ion b. positively charged ion
c. a negative electrode d. positive electrode

25. The electron has a charge and a very mass.
a. negative, small b. positive, small
c. negative, large d. positive, large

26. Radioactivity is
a. the spontaneous emission of radiation from unstable elements
b. the emission of light from certain substances after exposure
c. the spontaneous emission of radio waves from matter
d. the emission of light from matter when exposed to radio waves

27. Which person won two Nobel prizes, one in physics and one in chemistry, for work with radioactivity?
a. Antoine Henri Becquerel b. Marie Sklodowska Curie
c. Pierre Curie d. Linus Pauling

28. Which of the following is not one of the three types of radiation emitted from radioactive elements?
a. alpha b. beta, c. gamma, d. lambda,

29. Based on the experiments done by Marsden and Geiger using à particles and foil, Rutherford proposed that:
a. atoms are like bowls of positive pudding with negative raisins scattered about
b. atoms have very small, very dense positively charged nuclei and the rest of the atom is mostly empty space
c. atoms do not exist
d. none of the above

30. The proton
a. has the same mass and charge as the electron
b. has a smaller mass and the opposite charge as the electron
c. has a larger mass and the opposite charge as the electron
d. has a larger mass and the same charge as the electron

31. The number of protons in an atom is called the
a. atomic mass b. atomic number
c. atomic weight d. mass number

32. Isotopes are atoms of the same element with different numbers of:
a. neutrons b. protons c. electrons d. none of the above

33. The energy levels of electrons is analogous to:
a. a person on a swing
b. a pitcher throwing a baseball
c. a person climbing stairs
d. a parachutist in a free-fall

34. As the energy level of an electron increases, the electron's distance form the nucleus, on average,
a. increases b. decreases c. remains the same d. can not be predicted

35. The number of electrons in a neutral atom is equal to the
a. atomic mass b. atomic number c. atomic weight d. atomic number+1

36. The number of protons in a magnesium atom is
a. 12 b. 13 c. 24 d. 25

37. How many electrons are there in a neutral sulfur atom?
a. 16 b. 38 c. 47 d. 79

38. Which element is a noble gas?
a. Cl b. F c. Na d. Xe

39. The noble gases are a unique group of elements . They are recognized as unique due to the fact that they are
a. all gases at room temperature
b. extremely stable and unreactive
c. the most reactive member of their period
d. named after Nobel prize winners

40. All noble gases have electrons in their outer shell.
a. two b. four c. six d. eight

Essay Question: Please choose one of the following questions and write one well-organized, concise paragraph. (20 points)

I. What is the significance of the Law of Conservation of Mass in regards to waste disposal.

II. The third law of thermodynamics states that the universe is going towards higher and higher disorder. To combat this disorder, energy must be put into a system. Describe a 'system' in your life that demonstrates the validity of this law.

III. Describe both basic and applied research. Give an example of a discovery that came from each of these types of research.

IV. Describe the methods that Aristotle used to study the world around him. Give an example of one of his theories.