HS Sample Set 12, Round 16 from NSB
Identify all of the following three statements that are true of cyclohexane: 1) It is miscible with benzene; 2) The bond angles in the ring are sixty degrees; 3) It is more strained than cyclooctane.
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Lithium aluminum hydride would likely be used by a synthetic chemist for what type of reaction? W) Amide bond formation X) Nucleophilic substitution Y) Reduction Z) Aromatic substitution
W: W) Amide bond formation
X: X) Nucleophilic substitution
Y: Y) Reduction
Z: Z) Aromatic substitution
Answer: Y) Y) Reduction
A bag contains three red and three blue marbles. One marble is drawn, and then a second, without replacement. What is the probability of drawing one marble of each color?
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Solve the following system of three equations in three unknowns: x + y = 4, y + z = 1, and x + z = 13
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In humans, hyperfunctioning of the thyroid gland can result from which of the following conditions? W) Cushing’s syndrome X) Addison’s disease Y) Cretinism Z) Graves’ disease
W: W) Cushing’s syndrome
X: X) Addison’s disease
Y: Y) Cretinism
Z: Z) Graves’ disease
Answer: Z) Z) Graves’ disease
Identify all of the following three statements that are true of lancelets: 1) They possess a post-anal tail; 2) They possess pharyngeal slits; 3) Their musculature derives from mesoderm.
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Widmanstätten patterns are most commonly found in which of the following objects? W) Stony meteorites X) Iron meteorites Y) Moon rocks Z) Carbonaceous chondrites
W: W) Stony meteorites
X: X) Iron meteorites
Y: Y) Moon rocks
Z: Z) Carbonaceous chondrites
Answer: X) X) Iron meteorites
Lobate scarps on the surface of Mercury are a result of which of the following processes? W) Cooling X) Plate tectonics Y) Volcanism Z) Land tides
W: W) Cooling
X: X) Plate tectonics
Y: Y) Volcanism
Z: Z) Land tides
Answer: W) W) Cooling
To the nearest whole number of joules, how much work is done by a 4-newton-meter torque applied over one full revolution to a 3-kilogram wheel with radius 7 meters?
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The potential energy of the two atoms in a diatomic molecule is defined by the Lennard-Jones potential, \(U = \tfrac{A}{d^{12}} - \tfrac{B}{d^6}\). Identify all of the following three statements that are true of this system: 1) At equilibrium, force is minimized; 2) At equilibrium, potential energy is zero; 3) At equilibrium, force is zero.
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Researchers at SLAC lab are operating and collecting data from the orbiting Fermi telescope, which captures light from what region of the electromagnetic spectrum that is useful for studying Type II supernovae and pulsars?
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The London Penetration Depth best measures the penetration of which of the following quantities? W) Current X) External magnetic field Y) Alternating current Z) An external electric field
W: W) Current
X: X) External magnetic field
Y: Y) Alternating current
Z: Z) An external electric field
Answer: X) X) External magnetic field
What is 69 times 13?
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What is the cross product of vectors \(\mathbf{i} + 2\mathbf{j} + 3\mathbf{k}\) cross \(\mathbf{j}\)?
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An astronaut, who is 60 kilograms and initially at rest, is approached by a crate of supplies that is moving at 4 meters per second. When the crate is close, the astronaut pushes against it, accelerating him to 2 meters per second and slowing the crate down to 2.5 meters per second. What is the mass, in kilograms, of the crate?
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A 4-kilogram block is placed on top of a spring with a spring constant of 100 kilograms per second squared. To the nearest joule, how much energy will be released by the spring when the block is removed?
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Tephrochronology deals with age-dating what type of material? W) Carbonate shells X) Dead organisms Y) Volcanic ash Z) Ice-rafted debris
W: W) Carbonate shells
X: X) Dead organisms
Y: Y) Volcanic ash
Z: Z) Ice-rafted debris
Answer: Y) Y) Volcanic ash
Identify all of the following three statements that are true of fossil fuels: 1) Good reservoir rocks have high permeability; 2) Good cap rocks have low permeability; 3) Natural gas tends to form at shallower depths than oil.
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Methanol has a more negative standard change in enthalpy of formation than methane. Which of the following is true regarding their relative chemical stabilities? W) Methanol is more stable than methane X) Methanol is less stable than methane Y) Because both are composed of the same atoms, they are equally stable Z) Their stabilities cannot be compared with standard enthalpy changes
W: W) Methanol is more stable than methane
X: X) Methanol is less stable than methane
Y: Y) Because both are composed of the same atoms, they are equally stable
Z: Z) Their stabilities cannot be compared with standard enthalpy changes
Answer: Z) Z) Their stabilities cannot be compared with standard enthalpy changes
Acetone cyanohydrin is formed when a cyanide ion reacts with acetone. What atom is the electrophile in this reaction? W) Nitrogen on the cyanide ion X) Carbon at the 2 position on acetone Y) Carbon at the 1 position on acetone Z) Oxygen on acetone
W: W) Nitrogen on the cyanide ion
X: X) Carbon at the 2 position on acetone
Y: Y) Carbon at the 1 position on acetone
Z: Z) Oxygen on acetone
Answer: X) X) Carbon at the 2 position on acetone
De novo phasing is a technique that structural biologists at SLAC use to gather information about a new protein’s 3D shape. This technique involves the replacement of a single atom inside the protein with a traditionally non-proteinogenic atom with similar chemical behavior. In one example, the researchers replaced a sulfur atom with what? W) Nitrogen X) Selenium Y) Phosphorus Z) Arsenic
W: W) Nitrogen
X: X) Selenium
Y: Y) Phosphorus
Z: Z) Arsenic
Answer: X) X) Selenium
Los Alamos National Lab scientists are studying how microbes in the soil can slow down the spread of what long-lived radioisotope that is readily absorbed in the thyroid? W) Strontium-90 X) Iodine-131 Y) Cesium-137 Z) Iodine-129
W: W) Strontium-90
X: X) Iodine-131
Y: Y) Cesium-137
Z: Z) Iodine-129
Answer: Z) Z) Iodine-129
Which of the following forms of nitrogenous waste excretion is most energetically costly to produce? W) Ammonia X) Urea Y) Ammonium Z) Uric acid
W: W) Ammonia
X: X) Urea
Y: Y) Ammonium
Z: Z) Uric acid
Answer: Z) Z) Uric acid
During Western blotting, a blocking solution is often prepared. What is the primary function of the blocking solution? W) Conditioning of the PVDF membrane X) Limiting non-specific binding of antibodies Y) Preserving antibody-protein interactions Z) Quenching protein denaturation
W: W) Conditioning of the PVDF membrane
X: X) Limiting non-specific binding of antibodies
Y: Y) Preserving antibody-protein interactions
Z: Z) Quenching protein denaturation
Answer: X) X) Limiting non-specific binding of antibodies
What class of meteorites is composed of undifferentiated, spherical particles that are believed to contain primitive material from which rocky planets formed? W) Achondrites X) Chondrites Y) Iron meteorites Z) Pallasites
W: W) Achondrites
X: X) Chondrites
Y: Y) Iron meteorites
Z: Z) Pallasites
Answer: X) X) Chondrites
What is the spin-to-orbit resonance ratio of Mercury?
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If the graph of $$y = (x + 4)^2 + 3$$ is translated 2 units to the right and 4 units down, what are the coordinates of the vertex of the image?
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A 5-digit palindrome has 3 different digits and is divisible by 8. What is the largest such number?
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Plane polarized light with an intensity of $$I$$ passes through a filter that makes a 30-degree angle with respect to the angle of polarization. In terms of $$I$$, what is the intensity of the light after it passes through the filter?
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Identify all of the following three statements that are true regarding RLC circuits with an AC source: 1) At resonance, the source voltage and current are in phase; 2) The circuit’s Q factor is inversely proportional to its bandwidth; 3) At resonance, the voltage across the resistor equals the source voltage.
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Researchers at SLAC developed a microscopic rake that enables better mixing of deposited materials on surfaces, resulting in more efficient solar cells. Which of the following solar cells benefit from this invention? W) Polymer cell X) Thin-film cell Y) Wafer cell Z) Organic cell
W: W) Polymer cell
X: X) Thin-film cell
Y: Y) Wafer cell
Z: Z) Organic cell
Answer: W) W) Polymer cell
Due to the desire for extremely low neutron-absorption cross sections in nuclear-fuel-rod cladding, they are primarily composed of what metal?
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What type of phagocytic cell can primarily be found under mucosal surfaces and plays a primary role in responding to multicellular pathogens? W) Neutrophils X) Eosinophils Y) Dendritic cells Z) Macrophages
W: W) Neutrophils
X: X) Eosinophils
Y: Y) Dendritic cells
Z: Z) Macrophages
Answer: X) X) Eosinophils
A scientist is separating proteins using size-exclusion chromatography. Identify the relative order of elution from earliest to latest of the following proteins from the column: 1) Titin; 2) Myoglobin; 3) Hemoglobin; 4) Cytochrome c.
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Which of the following functional groups can be found in sucrose? W) Alcohol X) Amine Y) Aminal Z) Carboxyl
W: W) Alcohol
X: X) Amine
Y: Y) Aminal
Z: Z) Carboxyl
Answer: W) W) Alcohol
Which of the following techniques would most unambiguously determine the structure of a compound that contains stereocenters? W) Mass spectrometry X) X-ray crystallography Y) 1D NMR spectroscopy Z) Atomic absorption spectroscopy
W: W) Mass spectrometry
X: X) X-ray crystallography
Y: Y) 1D NMR spectroscopy
Z: Z) Atomic absorption spectroscopy
Answer: X) X) X-ray crystallography
What is the determinant of the 2-by-2 matrix with first row –3, –5 and second row 8, –2?
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Find the volume of the solid obtained by rotating about the y-axis the region bounded by $$y = x^2 - x^3$$ and $$y = 0$$.
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Fairy rings are associated with what division of fungi?
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A patient presents with the ability to understand language, but the inability to speak. What small region of the left frontal lobe might be damaged?
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A 9-volt battery with internal resistance of 1 ohm is connected to a lightbulb. If the potential drop across the lightbulb is 6 volts, then in watts, how much power is dissipated by the lightbulb?
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Water flows through a horizontally-level pipe at 4 meters per second, until it encounters a section where its static pressure decreases by 10 kilopascals. To the nearest whole number of meters per second, what is its new flow speed?
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Identify all of the following three rocks that would be classified as aphanitic: 1) Andesite; 2) Basalt; 3) Diorite.
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Place the following three rock types in increasing order of distance from shore at the time of deposition in a typical sedimentary sequence: 1) Shale; 2) Limestone; 3) Sandstone.
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Aspartame is an artificial sweetener composed of amino acids linked by what type of chemical bond?
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Identify all of the following three chemical moieties that are capable of having cis-trans isomerism: 1) Tetrahedral complex; 2) Alkene; 3) Square planar complex.
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