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Name Sci101/Fall02 Exam 3 Version A
1) Which of the following are electrically neutral?
A) proton B) electron C) neutron D) all of these E) none of these
Answer: C
2) Which of these atoms has the most mass?
A) lead B) iron C) hydrogen D) uranium E) All have the same mass.
Answer: D
3) What makes an element distinct?
A) the number of neutrons B) the number of electrons C) the total mass of all the particles
D) the number of protons E) none of these
Answer: D
4) Which has the greatest number of protons in its nucleus?
A) lead B) gold C) mercury D) silver
Answer: A
5) If two protons are removed from an oxygen nucleus, the result is
A) carbon. B) neon. C) helium. D) nitrogen. E) none of these.
Answer: A
6) The atomic number of an element is the same as the number of its
A) protons. B) nucleons. C) neutrons .D) neither of these.
Answer: A
7) Different isotopes of an element have different numbers of
A) neutrons. B) neutrinos. C) photons. D) protons. E) none of these.
Answer: A
8) The half-life on an isotope is one day. At the end of three days, how much of the isotope remains?
A) one-quarter B) none C) one-half D) one-eighth E) none of these
Answer: D
9) When an alpha particle is ejected from a nucleus, the nucleus then has less
A) mass. B) charge. C) both of these .D) neither of these.
Answer: C
10) There is a greater proportion of carbon-14 in
A) old bones B) new bones C) same in each.
Answer: B
11) Carbon-14 is produced in the atmosphere principally by
A) plants and animals. B) nitrogen bombardment. C) cosmic ray bombardment.
D) photosynthesis. E) none of these.
Answer: C
12) Most of the radioactivity we personally encounter comes from
A) fallout from past and present testing of nuclear weapons. B) medical X rays.
C) nuclear power plants. D) the natural environment.
Answer: D
13) Radioactivity in the world is something
A) as old as the world itself. B) relatively new.
Answer: A
14) It's impossible for a hydrogen atom to emit an alpha particle.
A) True B) False
Answer: A
15) A certain radioactive isotope placed near a Geiger counter registers 120 counts per minute. If the half-life of the
isotope is 1 day, what will the count rate be at the end of 4 days?
A) 5 counts/min B) 7.5 counts/min C) 30 counts/min D) 10 counts/min E) 15 counts/min
Answer: B
16) A solid is not considered fluid because
A) of the heavy nature of its atoms or molecules. B) of the fixed arrangement of its atoms or molecules.
C) its atoms or molecules are under too much pressure.
D) its atoms or molecules are bound as close together as possible.
Answer: B
17) Gases are so much easier to squeeze into smaller volumes than liquids or solids because
A) their atoms or molecules are already moving at high speeds. B) they are so much lighter.
C) there is so much space in between the submicroscopic particles.
D) they are always warmer than liquids or solids.
Answer: C
