Download PHYS 1400 Sample Exam Questions: Properties of Matter (Atoms) 1

PHYS 1400 Sample Exam Questions: Properties of Matter (Atoms)
1.
Aristotle believed
A) that the universe was unknowable. His philosophy stated that, because any human observer is
inherently biased, observations made by humans cannot be trusted to reveal truth.
B) that the universe was unknowable, but because human beings are simply not sufficiently
intelligent to understand what they observe, or to discover the truth in what they have observed.
C) that the universe could be understood. He was the first person to develop a philosophy based on
the idea that only through observation and testing could the natural world be described and
comprehended.
D) that the universe was knowable, but only through means of divine inspiration. Because an
observer is biased, knowledge and truth could only be gained passively, when the gods literally
poured the thoughts into your head like water into a bucket.
2.
What is the difference between an experiment and an observation?
A) An experiment requires that the experimenter not interfere with or manipulate the physical world;
an observation occurs when an observer acts on or interferes with something to see what will
happen.
B) Observing is recording what you see (or hear, whatever) without interfering (look, but don't
touch). Experimentation is intentionally acting on or manipulating something to see what
happens.
C) There is no difference between the two; both observing and experimenting are acting on or
manipulating the physical universe. The difference is simply an historical language convention: we
say that astronomers and biologists observe, but physicists and chemists experiment.
D) An experiment is what happens when you succeed: look what I did! Nobel Prize for me! An
observation is what happens when you fail: it wasn't me! I never touched anything! It just
exploded, I swear!
3.
The steps of the scientific method
A) are flexible; when science gets done in the real world, the steps may not be followed in order.
B) are rigid: science cannot make progress except when the steps are followed precisely and in
order.
C) are unimportant: the important thing about science is that once an idea becomes established, it is
immutable and does not ever change.
D) are mysterious: nobody really knows what the scientific method is. When something important
gets discovered, it's usually because the discoverer just got really lucky.
4.
What separates science from something like art or literature?
A) Nothing, really. A scientific paper in a peer-reviewed journal and a big-eyed kitten painted on
black velvet are both valid ways of describing the universe. Both are just somebody's opinion.
B) Science is rigid, but literature is flexible. A scientific paper must follow certain rules (like having
an introduction and a conclusion), but literature can be in any form. The content is not relevant,
just the format.
C) Scientific ideas must be tested before they can be accepted, and if any test proves the idea wrong,
the idea must be changed. Not so with art or music. You may not like to look at Picasso or listen
to Bach, but that does not make the paintings or the music wrong.
D) Science is something that people who are good at math do, because they are usually pretty
untalented at things like writing poetry or throwing pots. If scientists were better at playing the
guitar, they would all be in rock bands, because music or painting is a higher calling than, say,
discovering electrons or new planets.
5.
How does an hypothesis differ from a theory?
A) An hypothesis is a wild, crazy guess. A theory is an informed, or educated, guess. Neither has
been proven.
B) An hypothesis is an educated guess that has been tested. A theory is a random idea that can't be
proved.
C) An hypothesis is an educated guess. It can become a theory after is has been welltested and is not
shown to be false.
D) There is no difference; the words actually mean the same thing, but tend to be used differently.
People typically say "hypothesis" when they mean a respected idea, but call something they think
is crazy a "theory."
6.
How does a scientist choose between competing hypotheses?
A) Eenie, meenie, miney, moe: catch an hypothesis by the toe. If it hollers, let it go and try another
one. Maybe next time if you tap it on the shoulder politely instead of lunging at its feet it won't
holler so much.
B) A scientist usually chooses the hypothesis that fits best with his or her preconceived notions.
C) He may not really have to choose; as more experiments or observations are performed, some of
the competing hypotheses may be eliminated as they are shown to be false.
D) A scientist should not ever choose, because all hypotheses are equally valid. The point of science
is to keep an open mind, and you can't do that if you are eliminating some of the possibilities.
7.
Why do scientists use equations?
A) They are just showing off, trying to impress us with their so—called Fourier transforms and fancy
second—order partial differential equations. It makes them feel superior to confuse the rest of us
with complicated math stuff.
B) Science cannot be done without equations; the only way to find scientific answers is
mathematically.
C) Mostly because they are pretty geeky, and can't really communicate normally with words, like the
rest of us.
D) Equations are a concise and convenient way to express ideas, and can be used to make precise
predictions.
8.
Which of the following is an example of genuine science (as opposed to pseudoscience)?
A) Astronomy.
B) Astrology.
C) ESP.
D) Reincarnation.
9.
Why does Mendeleyev generally receive the credit for developing the periodic table of the elements,
even though Lothar Meyer came up with almost exactly the same table at almost exactly the same
time?
A) Because he was a Russian, and Meyer was German. In the middle of the 1860s, Germany was
known to be a haven for fakers and con men. Everybody just assumed that Meyer was bluffing.
B) Meyer's periodic table was just plain wrong. He asserted that the symbol Pb represented the
element peanut butter, and Cs stood for cheese. Maybe he was just hungry and needed an Sn
(Snickers).
C) Mendeleyev gets the credit because his table was based on the prior work of Dalton. Mendeleyev
used Dalton's predictions to expand the 65 known elements to the 118 we know today.
D) Mendeleyev used his periodic table to predict the existence of previously undiscovered elements.
For example, the element gallium was discovered after Mendeleyev's table indicated that an
element should exist with its specific properties.
10. What is energy?
A) Energy is the ability to do work. Whatever work is.
B) Energy is not the ability to do work; it is the ability to avoid doing any work at all.
C) Energy is a mystery. No one, not even brilliant guys like Newton or Einstein, really has a clue what
energy is.
D) Energy does not really exist; it is a hypothetical idea that scientists use to encompass many
different ideas that they simply do not understand or observations that they cannot explain.
11. When Democritus proposed the atomic theory of matter more than 2000 years ago, he suggested that
A) atoms were particles of matter too small to be seen. These atoms could not be split into smaller
pieces.
B) the four fundamental elements were earth, air, fire, and water. Anything could be made by mixing
these four substances in various ratios and combinations.
C) the weight ratio of hydrogen to oxygen in water was always 1:8.
D) the compound peanut butter was composed of equal parts peanuts and butter.
12. The atomic theory of matter
A) is relatively new, originating with Werner Heisenberg in the 1920s.
B) is one of Einstein’s great achievements from his best year, 1905.
C) revolutionized physics when Bohr proposed the quantum atom in the 1950s.
D) is over 2000 years old; Democritus proposed the existence of atoms in about 400 BC.
13. Dalton’s weight ratios, Brownian motion, and Einstein’s rates of diffusion
A) are direct proof that atoms exist.
B) are direct proof that atoms do not and cannot exist.
C) are indirect evidence that is consistent with atomic theory.
D) are indirect evidence that is inconsistent with atomic theory.
14. The electron was discovered
A) in 1987 by Hunter S. Thomson, who chronicled this work in Fear and Loathing in Las Vegas.
B) in 1911 by Ernest Rutherford, who was intent on disproving Bohr’s planetary model.
C) in 1897 by J.J. Thomson, who determined that cathode ray particles were too small to be ions.
D) in 1789 by Benjamin Franklin, during his famous kite-flying experiment.
15. The atomic nucleus was discovered
A) in 1911 by Ernest Rutherford, who bombarded a gold foil with particles to observe their path.
B) in 1906 by Einstein, using the photoelectric effect.
C) in 1897 by J.J. Thomson, who determined that cathode ray particles were too small to be ions.
D) in 1876 by Rutherford B. Hayes, nuclear physicist and 19th President of the United States.
16. How do we know that atoms really exist?
A) Easy; you can see them with your naked eye. They are as big as the period at the end of this
sentence.
B) They don't; an atom is not a real physical object. Atoms are a theoretical construct that allows us
to describe the behavior of matter, but atoms do not exist as real objects in the real universe.
C) There is indirect evidence: Brownian motion. If that's not enough for you, there is also direct
evidence: using an electron microscope, you can obtain the actual image of an atom.
D) There is no direct evidence for the existence of atoms; they may or may not exist, we just don't
know yet. That's why it's called the Atomic Theory, not the Atomic Hypothesis!
17. How do we know that atoms are motion?
A) Easy; you can see them move. This is so obvious, you don’t even need a microscope.
B) Diffusion: you can watch an ink drop spread through a glass of water, or smell the cookies baking.
C) They aren’t; if atoms were in motion, then you could not make them stick together long enough to
make anything at all, and certainly not a fresh batch of cookies.
D) We don’t; they may be in motion, or they may not. They are too small to observe, so nobody
knows just exactly what the atoms are doing.
18. How did Einstein contribute to our understanding of atoms?
A) He did not. His only contribution to physics, general relativity, has nothing to do with atoms.
B) He observed that particles suspended in water appear to move, even though they are not alive.
C) He calculated the ratio of hydrogen to oxygen in water, and found that it was always 1:8.
D) He calculated rates of diffusion, which could be measured experimentally.
19. What's so important about Max vonLaue and his shooting a beam of xrays at a piece of metallic foil?
A) This experiment demonstrated the existence of the atomic nucleus.
B) This experiment proved that electrons can only exist in specific orbits.
C) Nothing really, but the beam happened to accidentally hit Einstein square in the back of the
head...now you know why he always had that crazy hairdo!
D) Not only did it show that atoms really exist, it also revealed that longrange order was possible,
and that different metals could have different crystal structures.
20. Which of the following is not true about atoms?
A) Atoms are composed of protons, neutrons and electrons.
B) Your brain contains atoms that were once part of Albert Einstein.
C) There are atoms in your body that are billions of years old.
D) If you added up the number of atoms in the universe, there would be about 117.
21. Protons
A) have a positive charge.
B) have the same mass, but opposite charge as electrons.
C) are bound in the nucleus of atoms, with electrons acting as “glue.”
D) are found in shells orbiting the nucleus.
22. Neutrons
A) have a negative charge.
B) have the same mass as electrons.
C) are found in the nucleus of atoms.
D) are found in shells orbiting the nucleus.
23. Electrons
A) have a positive charge.
B) have an extremely small mass, compared to protons or neutrons.
C) orbit randomly, and can be anywhere at any distance from the nucleus.
D) are the “glue” that keeps the neutrons orbiting the nucleus.
24. Beryllium has an atomic number of 4. This means
A) there are 4 particles in the nucleus: 2 protons, and 2 neutrons.
B) there are 4 particles in the entire atom: 1 proton, 1 neutron, and 2 electrons.
C) there are 4 protons in the nucleus.
D) each atom of beryllium weighs 4 grams.
25. Sodium has an atomic number of 11, and an atomic weight of 22.99. Why isn’t the weight exactly 22?
A) The atoms will have 11 protons in their nucleus, but may have more than 11 electrons.
B) There will be 11 protons, but some isotopes of sodium may have more than 11 neutrons, which
increases the average weight.
C) Not all protons weight the same; some of the protons weigh more, increasing the atomic weight.
D) None of these explanations is correct!
26. Explain the difference between an atom and a molecule.
A) Another annoying instance of two words that actually mean the same thing, like hypothesis and
theory, or precision and accuracy.
B) An atom consists of two or more molecules joined loosely together. They may be separated
mechanically.
C) A molecule is a substance that cannot be broken down into a simpler substance, like gold or iron.
D) A molecule consists of two or more atoms chemically bonded together. The atoms may be the
same kind, or they may be different types.
27. Most of the oxygen in the earth's atmosphere is in the form of
A) atoms. Single oxygen atoms, because oxygen does not combine with anything.
B) diatomic molecules. One oxygen atom easily combines with a second to form a molecule.
C) triatomic ozone. Diatomic oxygen molecules exist, but are much rarer than 3-atom ozone
molecules.
D) quadratomic frozone molecules. When you stick four oxygen atoms together, they make solid
cubes of ice.
28. The most abundant element in the universe is
A) hydrogen.
B) oxygen.
C) iron.
D) uranium.
29. How is a mixture different from compound?
A) A mixture consists of two or more things that are chemically bonded together, like table salt
(NaCl).
B) The components of a mixture can be combined or separated mechanically, like by sifting.
C) The components of a mixture must be heated to separate them, like you have to boil water to
separate the hydrogen and the oxygen.
D) A mixture is always solid, but a compound is always liquid. For example, the liquid water in your
glass is a compound, but the ice cubes are a mixture.
30. An
A)
B)
C)
D)
element is
composed of at least two different substances that are bonded chemically.
composed entirely of like atoms, having a single type of atomic structure.
composed of different substances, and can be separated mechanically.
impossible to isolate in the lab, so just a hypothetical chemical construct.
31. The principle of conservation of mass states that
A) atoms cannot be created, destroyed, moved, or recombined in any way. Mass is completely static.
B) atoms can be created or destroyed, but not moved or recombined.
C) atoms can be created, but they cannot be destroyed. They can be moved, but they cannot be
recombined.
D) however much mass exists in the universe now, that's how much there has always been. Matter
cannot be created or destroyed.
32. How did Antoine Lavoisier demonstrate the conservation of mass?
A) He took a sheet of paper and weighed it. Then he took the same paper to another laboratory and
weighed it again, on a different scale. Because it weighed the same, he concluded that moving a
mass did not change it.
B) He used his finest scales. He weighed a woman and a duck. He concluded that because she
weighed the same as the duck, that she was a witch. The villagers burned her.
C) He burned a scrap of paper in a closed container. By weighing the container before, and again
after, he was able to show that even though the paper was gone, there was still the same amount
of matter in the box.
D) He counted the number of nitrogen molecules in one closed flask. Then he counted the number of
oxygen molecules in a second flask. Because the number was the same for both, he concluded
that mass is conserved.
33. What exactly is Avogadro's Principle?
A) The idea that everything in the universe is made up of the same number of atoms, no matter what
it is. For example, a blue whale and a bluegill are both made of exactly 6.02x1023 atoms. The
atoms of the blue whale are just bigger, that's all.
B) Not everything is made of the same number of atoms, but if you isolate equal volumes of different
gases, and they are at the same temperature, then they will have the same number of molecules.
C) This is a very complicated idea: the number of each different type of atom or molecule that makes
up an object has to be the same. So, a human being is made of 6.02x1023 water molecules,
6.02x1023 carbon atoms, 6.02x1023 calcium atoms, etc.
D) The idea that there are exactly 6.02x1023 atoms in the entire universe. everything that exists has
to made of these atoms, so they have to be moved around and recombined with each other
frequently.
34. Atomic mass unit?
A) One carbon atom weighs 1amu, which is 12 grams.
B) A hydrogen atom weighs exactly 1amu, which is essentially the mass of a proton.
C) The weight of an atom. Every atom has a unique atomic mass unit, because every atom is
different.
D) This is that curved tower thing you see at nuclear power plants. It's where the atomic energy is
created.
35. The periodic table
A) organizes the elements in both rows and columns that share similar properties.
B) is a vertical arrangement of the elements. The columns are related, but not the rows.
C) is a random arrangement of elements and compounds that are relatively rare on earth.
D) is a horizontal arrangement of the elements. The rows are related, but not the columns.
36. Find the element Indium (In) on the attached periodic table. What is the atomic number of In?
A) 49. It has exactly 49 neutrons in its nucleus.
B) 49. There are exactly 49 protons in its nucleus.
C) 114.8. There are exactly 114.8 protons in its nucleus.
D) 114.8. There are exactly 49 protons in its nucleus, but it may have either 65 or 66 neutrons, so
the atomic number is an average.
37. What is the atomic weight of In?
A) 49. Each proton and neutron in the nucleus weighs exactly 1amu, and there are 49 of them in the
nucleus.
B) 49. Each proton and neutron weighs exactly 0.5amu, and there are 49 of each in the nucleus.
C) 114.8. Each proton and neutron in the nucleus weighs 1amu. The weight has a decimal because
some isotopes exist with more or fewer neutrons, so this number is an average value.
D) 114.8. Each proton and neutron in the nucleus weighs exactly 1amu, and there are 114.8 total
particles.
38. Find the element titanium (Ti.) on the attached periodic table. What is the atomic number of Ti?
A) 22. It has exactly 22 protons in its nucleus.
B) 22. There are exactly 11 protons and 11 neutrons in the nucleus.
C) 22. There are 7 protons and 7 electrons, but it has 8 neutrons.
D) 47.87. This is the total number of particles in the nucleus. It has a decimal because some isotopes
exist with more or fewer neutrons, so this number is an average value.
39. What is the atomic weight of Ti?
A) 47.87. Each proton and neutron in the nucleus weighs exactly 1.088amu, and there are 22 of each
in the nucleus.
B) 47.87. Each proton and neutron in the nucleus weighs exactly 2.176amu, and there are 11 of each
in the nucleus.
C) 47.87. Each proton and neutron in the nucleus weighs exactly 1amu. The weight has a decimal
because some isotopes exist with more or fewer neutrons, so this number is an average value.
D) 22. Each proton and neutron in the nucleus weighs exactly 1amu, and there are 22 total particles.
40. Which element comes the closest to having twice the atomic weight of Ti?
A) Zirconium (Zr).
B) Molybdenum (Mo).
C) Ruthenium (Ru).
D) Technetium (Tc).
41. When a hydrogen nucleus is fused with a lithium nucleus, the result is
A) a really big mess.
B) a helium nucleus.
C) a beryllium nucleus.
D) an unobtanium nucleus.
42. What is antimatter?
A) Nothing; just science fiction jargon from the Start Trek universe!
B) Antimatter particles have the same mass, but opposite charge as particles of matter.
C) No; antimatter particles have the same charge, but opposite mass as matter particles!
D) Protons and electrons are a particle/anti-particle pair because they have opposite charges. The
mass doesn’t matter.
43. What are quarks?
A) More Star Trek nonsense! The Ferengi unit of acquisition is called a quark.
B) No, this is Star Wars trivia: Boba Fett’s brand of jet pack was a Quark THX 1138.
C) On the planet Arrakis, the Fremen drink a distilled version of spice called quark.
D) Quarks are the subatomic particles that make up protons and neutrons.
44. And what about dark matter?
A) It’s the stuff in the antimatter containment field that surrounds the warp core. Can we please stop
with the Star Trek now?
B) It’s nothing special--just regular matter that happens to be dark in color, like charcoal.
C) It’s matter that hasn’t been observed, but is predicted to exist by the effect it has on stars and
galaxies. There seems to be an awful lot of it in the universe.
D) It opposes the Force; this is what ultimately turns Anakin Skywalker away from the Jedi path.