CHEMISTRY 100

EXAM 1c/ Fall 2000- 5 Oct ‘00

Name_______________________ x= correct answer

1. Technology is mainly concerned with “how-to” information such as recipes and processes. Science is concerned mainly with
a. bombs
b. finding UFOs
xc. explanations of natural phenomena
d. debunking religion

2. A theory is
a. an experiment b. tentative c. explanatory x d. b&c

3. Experiments are
a. explanations xb. tests c. authoritative statements d. declarations by politicians

4. All information that is scientific information is considered to be
a. tentative b. testable c. explanatory xd. all above

5. Theories
xa. are testable b. are not questioned once established c. are not falsifiable d. b&c

6. Mass
a. and weight are not always the same
b. is not changeable (except in extreme circumstances such as nuclear reactions)
c. is measured in grams
xd. all above

7. The density of a 150 gram object that has a volume of 25 mL is
a. 6 b. 0.17 gram/mL xc. 6 g/mL d. 3750 g/mL e. 3750

8. In order to find the density of an irregular object, one can use water displacement in some circumstances. A student had a graduated cylinder into which she placed 45 mL.
She then put the object into the water. It sank to the bottom of the water. The water level now read 56 mL. Some data that we can glean from the activities of the student are (is):
xa. the object is more dense than water
b. the object has a volume of 56 mL
c. given only the above data we can calculate density
d. all above are true


9. Temperature is measured in
a. calories b. degrees Celsius c. Joules d. all above xe. a& c above ONLY

10. The main difference between temperature and heat is
a. actually there is no difference
xb. heat requires knowledge of quantity of matter, temperature does not
c. heat is measured in kilograms, temperature in liters
d. all above

11. If you measure mass you need to use the following units
a. seconds
b. degrees Celsius
c. liters
d. meters
xe. kilograms

12. To convert milliliters (mL) to liters (L) one has the conversion factor 1000 mL = 1 L.
The correct factor label or dimensional analysis set-up to convert 60 mL to L is:
a. x= 1000 mL x 60 mL/ 1L

b. x= 60mL x 1000mL/ 1L

xc. x= 60 mL x 1L/1000mL

d. x= 1L x 1000mL/60 mL

13. A scientific fact is
a. an explanation
xb. an observation such as water freezes at 0 Celsius and 1 Atm. pressure
c. tentative
d. testable
e. b,c,d above

14. A compound would be
xa. NO b. Co c. Li d. Mg

15. An element would be
a. S₈ b. Al c. P₄ d. SO xe. a,b,c above

16. Given the reaction O_{2 +} 2H_{2 =} 2H₂O
32 g 4g 36 g
The masses shown leave no leftover O or H. All H & O are converted to water.
a. using 8 g of H should double the mass of water produced
b. adding 64 g of O should double the mass of water produced
xc. adding both 64g of O and 8g of H should double the mass of water produced
d. none above

17. Vitamin C (ascorbic acid) produced by oranges is
xa. Identical in composition to vitamin C produced in a factory
b. Not the same in composition as vitamin C produced in a factory
c. much better because it is natural
d. has a different formula from vitamin C produced in a factory

18. Compounds that seem to illustrate the law of multiple proportions are
a. H₂O₂ H₂O b. CO CO₂ c. NaOCl NaOBr x d. a&b only

19. If a reaction occurs with the definite proportions shown below:
C + O₂ = CO₂
24g 64g

Then we can expect _____ of product.
a. 44g b. 38 g c. 32 g xd. 88 g

20. In experiment 1 we used CuSO₄, NaCl, H₂O, and Al. Since we did not exclude air, we also involved N, CO₂, and Ar.
a. SO₂ could not have been the gas
xb. rust, Fe(OH)₃ could not be produced
c. Cu could be the brown product
d. b&c above

<sub>21. Chemical reactions
a. involve no creation of new atoms
b. involve the loss of some atoms
c. involve rearrangement of atoms- no loss or gain
d. involve new substances being formed
xe. a&c&d above

22. The electron configuration for the ground state of F, atomic number 9 is</sub>
a. 1s²2s²2s²2p³3s² b. 1s¹2s²2p⁶ xc. 1s²2s²2p⁵ d. 1s²2s¹2p<sup>6

23. The number of protons in F atoms is: (atomic #= 9, atomic mass=19)
a. 19 x b. 9 c. 10 d. 28

24. Na is in the group of elements called
a. nonmetals b. transition metals xc. alkali metals d. halogens

25. Elements (by atomic number) that we expect to react in a similar way are
xa. 11, 19, 87 b. 11, 12, 13 c. 15, 16, 18 d. 84, 85, 86

26. There are at least two isotopes of uranium, U-234 and U-235.
a. These isotopes do not react alike in a chemical reaction
b. these isotopes have different numbers of electrons
c. these isotopes have different numbers of protons
xd. these isotopes have different numbers of neutrons

27. The radiation type that goes the least distance in air is
a. alpha b. beta c. gamma d. all go the same distance

28. Radioactive dating of artifacts by C-14
a. relies on tree rings for calibration
b. can give inconclusive results when the tested material is contaminated
c. depends on the neutrons emitted by the sun
xd. all above

29. A bomb rated at 1000 tons of TNT is called a one ______________bomb.
a. critical mass xb. kiloton c. megaton d. transmutation

30. Given an isotope with a half life of 2 seconds and an initial amount of 1000g, how much will remain after 6 sec?
a. 1000g b. 500g c. 250g xd. 125 g e. 62.5g</sup>

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