HS Sample Set 8, Round 17 from NSB
In a hydrogen fuel cell, two moles of H₂ are oxidized by one mole of O₂ to form two moles of water. If the cell is 100% efficient, how many moles of electrons are transferred in this process?
Acceptable Answers:
The polymerization of a 1,3-diene will produce a material that can be used to make which of the following polymers? W) Nylon X) Rubber Y) Styrene Z) Thermoplastic
W: W) Nylon
X: X) Rubber
Y: Y) Styrene
Z: Z) Thermoplastic
Answer: X) X) Rubber
Which of the following correctly describes why antifungal medications are often harder to design than antibacterials? W) Antifungals must target peptidoglycan X) Both fungi and humans are eukaryotes Y) Bacteria and humans have similar cellular structures Z) Most antifungals target chitin-building enzymes
W: W) Antifungals must target peptidoglycan
X: X) Both fungi and humans are eukaryotes
Y: Y) Bacteria and humans have similar cellular structures
Z: Z) Most antifungals target chitin-building enzymes
Answer: X) X) Both fungi and humans are eukaryotes
Tunicamycin is a drug produced by some bacteria. It is used as a tool by molecular biologists because it induces eukaryotic cells to arrest at the G₁ checkpoint of the cell cycle. Using this information, which of the following would you expect to observe in a tunicamycin-arrested cell? W) Activated APC protein X) Chiasmata Y) Replication bubbles Z) Spindle fibers
W: W) Activated APC protein
X: X) Chiasmata
Y: Y) Replication bubbles
Z: Z) Spindle fibers
Answer: W) W) Activated APC protein
Power companies estimate the over-time cost of designing, building, operating, and decommissioning a power plant in order to calculate which of the following? W) Intrinsic cost X) Comprehensive fuel cost Y) Levelized cost Z) Future-versus-present earnings
W: W) Intrinsic cost
X: X) Comprehensive fuel cost
Y: Y) Levelized cost
Z: Z) Future-versus-present earnings
Answer: Y) Y) Levelized cost
Identify all of the following three changes that would increase the half-life of a first-order reaction: 1) Increasing the starting concentration 2) Decreasing the starting concentration 3) Increasing the rate constant
Choices:
Correct Answers:
Which of the following clays has the highest cation exchange capacity (CEC)? W) Kaolinites X) Vermiculites Y) Chlorides Z) Allophanes
W: W) Kaolinites
X: X) Vermiculites
Y: Y) Chlorides
Z: Z) Allophanes
Answer: X) X) Vermiculites
Which two planets in our solar system have the highest fraction of methane in their atmospheres?
Acceptable Answers:
Which of the following is correct about the symmetry of even functions? W) They are symmetric about the y-axis X) They are symmetric about the x-axis Y) They are symmetric about the origin Z) They do not necessarily have symmetry
W: W) They are symmetric about the y-axis
X: X) They are symmetric about the x-axis
Y: Y) They are symmetric about the origin
Z: Z) They do not necessarily have symmetry
Answer: W) W) They are symmetric about the y-axis
For a line passing through the point (1, 0, −1) and parallel to the vector (2, 1, 4), give the parametric equations for x, y, and z.
Acceptable Answers:
Amniotes became very well adapted to life on land. Which of the following is not an adaptation of amniotes to a terrestrial existence? W) Eggs resistant to desiccation X) Buccal pumping Y) Water-conserving kidneys Z) Thoracic breathing
W: W) Eggs resistant to desiccation
X: X) Buccal pumping
Y: Y) Water-conserving kidneys
Z: Z) Thoracic breathing
Answer: X) X) Buccal pumping
What facial muscle functions to enable blinking? W) Zygomaticus X) Orbicularis oculi Y) Orbicularis oris Z) Corrugator supercillii
W: W) Zygomaticus
X: X) Orbicularis oculi
Y: Y) Orbicularis oris
Z: Z) Corrugator supercillii
Answer: X) X) Orbicularis oculi
“Soda-lime” glass accounts for 90% of the glass produced and can be made by mixing a modifier, or flux, with sand. Which of the following is an example of a soda-lime glass modifier? W) SiO₂ X) Ca(OH)₂ Y) Na₂O Z) MgO
W: W) SiO₂
X: X) Ca(OH)₂
Y: Y) Na₂O
Z: Z) MgO
Answer: Y) Y) Na₂O
Categorize each of the following four examples of isomerism as either structural isomerism or stereoisomerism: 1) Geometrical 2) Ionization 3) Polymerization 4) Optical
Acceptable Answers:
Which of the following laws or principles gives a physical interpretation for the sign convention used in Faraday’s law of induction? W) Lenz’s law X) Ampère’s law Y) Coulomb’s law Z) Gauss’s law
W: W) Lenz’s law
X: X) Ampère’s law
Y: Y) Coulomb’s law
Z: Z) Gauss’s law
Answer: W) W) Lenz’s law
By number, give all of the following three statements that are true of Carnot engines: 1) Carnot’s theorem limits the efficiency of engines to less than that of a Carnot engine 2) The Carnot cycle consists of only reversible steps 3) The concept of entropy arose from the limits stated by the Carnot cycle
Choices:
Correct Answers:
Which of the following describes the ratio between the distance from a point to the center of a black hole and the circumference of a circle around the black hole? W) Less than π X) Equal to π Y) Greater than π Z) Undefined
W: W) Less than π
X: X) Equal to π
Y: Y) Greater than π
Z: Z) Undefined
Answer: Z) Z) Undefined
How much volcanic material, in cubic kilometers, does a volcano have to eject to be considered an 8 on the Volcanic Explosivity Index (VEI)?
Acceptable Answers:
What fluid, produced by ependymal cells, fills the space between the arachnoid and the pia mater as well as the ventricles of the brain?
Acceptable Answers:
Bungarotoxin is a fast-acting lethal toxin that is the primary component of venom from the South Asian snake called a krait. It blocks nerve transmission at cholinergic synapses by competing with acetylcholine to bind irreversibly at the acetylcholine receptor. Which of the following would be least likely to also impact nerve transmission at the cholinergic synapses? W) A drug floods the synapse with a molecule that resembles acetylcholine and is able to bind at the acetylcholine receptor, but cannot be recognized by acetylcholinesterase X) A chemical covalently binds to the acetylcholine receptor and is not easily inactivated Y) A chemical covalently bonds acetylcholinesterase at the enzyme active site Z) A drug increases the level of acetylcholinesterase present at the synapse
W: W) A drug floods the synapse with a molecule that resembles acetylcholine and is able to bind at the acetylcholine receptor, but cannot be recognized by acetylcholinesterase
X: X) A chemical covalently binds to the acetylcholine receptor and is not easily inactivated
Y: Y) A chemical covalently bonds acetylcholinesterase at the enzyme active site
Z: Z) A drug increases the level of acetylcholinesterase present at the synapse
Answer: Z) Z) A drug increases the level of acetylcholinesterase present at the synapse
Under what arithmetic operation is the set of even integers NOT closed?
Acceptable Answers:
An object is moving along a line in such a way that its position \(s\) at time \(t\) seconds is given by \[ s = 4t^3 - 12t^2 + 24t. \] Determine the minimum velocity of the object, in units per second.
Acceptable Answers:
Which of the following processes is used to produce additional ATP for the light-independent reactions of photosynthesis? W) Cyclic electron flow X) Lactic acid fermentation Y) Glycolysis Z) Beta oxidation
W: W) Cyclic electron flow
X: X) Lactic acid fermentation
Y: Y) Glycolysis
Z: Z) Beta oxidation
Answer: W) W) Cyclic electron flow
Assume we have two inlets to a hydroelectric plant’s turbines: one inlet is at 50 m depth, and the second inlet is at 80 m depth. How much greater, by percentage, is the pressure at the deeper compared to the shallower one?
Acceptable Answers:
Identify all of the following four types of reactions that follow Zaitsev’s rule: 1) SN1 2) SN2 3) E1 4) E2
Choices:
Correct Answers:
Identify all of the following three statements that are true of nuclear chemistry: 1) Helium has a higher binding energy per nucleon than uranium 2) Alpha particles have a +1 charge 3) Beta-minus decay usually occurs in nuclei with an excess number of neutrons
Choices:
Correct Answers:
All except which of the following can act as direct substrates for the production of acetyl CoA? W) Lactate X) Amino acids Y) Fatty acids Z) Ketone bodies
W: W) Lactate
X: X) Amino acids
Y: Y) Fatty acids
Z: Z) Ketone bodies
Answer: W) W) Lactate
Which of the following enzymes is unique to gluconeogenesis? W) PEP carboxykinase X) Pyruvate kinase Y) Hexokinase Z) Phosphofructokinase
W: W) PEP carboxykinase
X: X) Pyruvate kinase
Y: Y) Hexokinase
Z: Z) Phosphofructokinase
Answer: W) W) PEP carboxykinase
What is the name for the topography that is created through extension of crust, producing distinct horsts and grabens?
Acceptable Answers:
In the unified model of active galactic nuclei (AGN), what is the most important variable that determines what class of AGN is observed? W) Orientation angle X) Metallicity Y) Supermassive black hole age Z) Galaxy type
W: W) Orientation angle
X: X) Metallicity
Y: Y) Supermassive black hole age
Z: Z) Galaxy type
Answer: W) W) Orientation angle
The presence of what class of compounds in nuclear reactors slows down the neutrons in the core, preventing the development of a potential nuclear bomb?
Acceptable Answers:
DO NOT ACCEPT:
What extremely powerful biological oxidizing agent is used in photosynthesis to oxidize water and is named for its absorption maximum in the red part of the visible spectrum?
Acceptable Answers:
Two spheres with radii of 2 and 8 are resting on a tabletop so that they are touching. How far apart are their points of contact on the table? W) 2 X) 4 Y) 8 Z) 9
W: W) 2
X: X) 4
Y: Y) 8
Z: Z) 9
Answer: Y) Y) 8
You are given that \(xy = 6\) and \(x^2y + xy^2 + x + y = 63\). Calculate \(x^2 + y^2\).
Acceptable Answers:
Identify all of the following three experiments that demonstrate the particle nature of light: 1) Photoelectric effect 2) Dual-slit experiment 3) Davisson–Germer experiment
Choices:
Correct Answers:
Which of the following is NOT featured in the Bohr model of the atom? W) Quantized energy levels X) Densely packed nucleus Y) Atomic orbitals Z) Electrostatic attraction
W: W) Quantized energy levels
X: X) Densely packed nucleus
Y: Y) Atomic orbitals
Z: Z) Electrostatic attraction
Answer: Y) Y) Atomic orbitals
During starvation, muscles convert most of the amino acids released from muscle breakdown to what two specific amino acids for use in gluconeogenesis? W) Arginine and glycine X) Arginine and glutamine Y) Alanine and glutamine Z) Glutamine and glycine
W: W) Arginine and glycine
X: X) Arginine and glutamine
Y: Y) Alanine and glutamine
Z: Z) Glutamine and glycine
Answer: Y) Y) Alanine and glutamine
If you were to selectively extract protein molecules from the H-zone of a sarcomere, which of the following would be found in the extract? W) Actin X) Myosin Y) Titin Z) Tropomyosin
W: W) Actin
X: X) Myosin
Y: Y) Titin
Z: Z) Tropomyosin
Answer: X) X) Myosin
Identify all of the following four elements that would burn red when subjected to a flame test: 1) Lithium 2) Selenium 3) Barium 4) Calcium
Choices:
Correct Answers:
A particular polymer has a chain length of 8. If the same conditions were used to create another polymer, with the only difference being that a difunctional initiator will be used, what would the resulting chain length be?
Acceptable Answers:
Two planes are orthogonal to each other. How many lines exist that are a given fixed distance \(d\) from both of these planes?
Acceptable Answers:
Evaluate the following expression: \[ \displaystyle \sum_{n=1}^{14} n^2. \]
Acceptable Answers:
By number, rank the following three systems of materials, from lowest to highest, in terms of their coefficients of kinetic friction: 1) Rubber on concrete 2) Human joints 3) Ice on ice
Choices:
Correct Order:
Which of the following statements is correct about the behavior of black bodies? W) At high enough temperatures, black bodies will stop emitting in the microwave region X) The Stefan–Boltzmann law relates the power radiated by a black body to temperature squared Y) Approximating a human as a black body shows that most of a person’s energy is radiated away as ultraviolet light Z) Wien’s law can be used to predict the color of a black body
W: W) At high enough temperatures, black bodies will stop emitting in the microwave region
X: X) The Stefan–Boltzmann law relates the power radiated by a black body to temperature squared
Y: Y) Approximating a human as a black body shows that most of a person’s energy is radiated away as ultraviolet light
Z: Z) Wien’s law can be used to predict the color of a black body
Answer: Z) Z) Wien’s law can be used to predict the color of a black body
What was the principle reason that the Kapteyn model and the Shapley model of the size of the Galaxy were incorrect? W) They only examined the distribution of stars and failed to examine the distribution of globular clusters X) They used data that was not sensitive enough to detect the faintest stars in the Galaxy Y) They failed to account for extinction due to dust Z) They only examined the distribution of globular clusters and failed to examine the distribution of stars
W: W) They only examined the distribution of stars and failed to examine the distribution of globular clusters
X: X) They used data that was not sensitive enough to detect the faintest stars in the Galaxy
Y: Y) They failed to account for extinction due to dust
Z: Z) They only examined the distribution of globular clusters and failed to examine the distribution of stars
Answer: Y) Y) They failed to account for extinction due to dust
Which of the following sets of values best approximates an average micrite limestone in a ternary diagram with end members (1) allochemical grains, (2) chemical cement, (3) microcrystalline matrix? W) (1) 10%, (2) 90%, (3) 0% X) (1) 25%, (2) 0%, (3) 75% Y) (1) 75%, (2) 10%, (3) 15% Z) (1) 50%, (2) 45%, (3) 5%
W: W) (1) 10%, (2) 90%, (3) 0%
X: X) (1) 25%, (2) 0%, (3) 75%
Y: Y) (1) 75%, (2) 10%, (3) 15%
Z: Z) (1) 50%, (2) 45%, (3) 5%
Answer: X) X) (1) 25%, (2) 0%, (3) 75%