HS Sample Set 15, Round 13 from NSB
The drying step of the freeze-drying process is an example of what type of phase change?
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What are the IUPAC names of the products of the reaction between hydroiodic acid and lithium sulfide?
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The unit formed by multiplying pounds-force times seconds can be used to measure which of the following quantities? W) Momentum X) Angular momentum Y) Energy Z) Force
W: W) Momentum
X: X) Angular momentum
Y: Y) Energy
Z: Z) Force
Answer: W) W) Momentum
A parallel-plate capacitor is being used to store energy between its plates. If the potential difference between the plates is doubled and the charge on the capacitor is tripled, by what number will the energy stored be multiplied?
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What are the two largest galaxies in the Local Group?
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Which of the following best describes the blackbody curve of the Sun plotted as increasing wavelength versus intensity? W) Symmetric curve about λ_max X) Discrete line at λ_max Y) Steeply sloping below λ_max, gently sloping above λ_max Z) Gently sloping below λ_max, steeply sloping above λ_max
W: W) Symmetric curve about λ_max
X: X) Discrete line at λ_max
Y: Y) Steeply sloping below λ_max, gently sloping above λ_max
Z: Z) Gently sloping below λ_max, steeply sloping above λ_max
Answer: Y) Y) Steeply sloping below λ_max, gently sloping above λ_max
A function f maps from set A to set B, and a function g maps from set B to set C. If f is injective, and g is bijective, which of the following properties must hold for the composition g ∘ f? W) Bijective X) Injective Y) Surjective Z) Nothing can be established about g ∘ f
W: W) Bijective
X: X) Injective
Y: Y) Surjective
Z: Z) Nothing can be established about g ∘ f
Answer: X) X) Injective
What is the cube of the complex number 5 + 2i?
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A cell that fails to pass the G1 checkpoint in the cell cycle will enter what quiescent or senescent state?
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Crossing over during meiosis can be seen under a microscope as an X-shaped structure called what?
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Los Alamos National Lab scientists are fabricating nanoparticles to produce terahertz radiation. The terahertz band is best described as lying between what two regions of the electromagnetic spectrum? W) Microwave and infrared X) Infrared and visible Y) Visible and ultraviolet Z) Ultraviolet and X-ray
W: W) Microwave and infrared
X: X) Infrared and visible
Y: Y) Visible and ultraviolet
Z: Z) Ultraviolet and X-ray
Answer: W) W) Microwave and infrared
Scientists at the Joint BioEnergy Institute are studying how organisms synthesize secondary metabolites such as doxycycline, erythromycin, and aflatoxin. These are all part of what group of metabolites?
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What general type of chemical reaction involves two or more substances combining to form a single product?
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According to MO theory, which of the following orbitals is the LUMO acceptor orbital for the major cycloaddition reaction between butadiene and ethylene? W) Butadiene π* X) Butadiene π Y) Ethylene π* Z) Ethylene π
W: W) Butadiene π*
X: X) Butadiene π
Y: Y) Ethylene π*
Z: Z) Ethylene π
Answer: Y) Y) Ethylene π*
A capacitor is charged by applying a voltage that linearly increases with time. Which of the following describes the dependence of the stored electric potential energy with time? W) Square root X) Constant Y) Linear but not constant Z) Quadratic
W: W) Square root
X: X) Constant
Y: Y) Linear but not constant
Z: Z) Quadratic
Answer: Z) Z) Quadratic
The decay series of Uranium-238 eventually brings it to Uranium-234. What is the sum of the number of alpha- and beta-decay events that it takes for an atom of Uranium-238 to become Uranium-234?
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What is the product of the complex number 5 + 3i and its conjugate?
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What is the standard deviation of the following list of 5 numbers: 6, 7, 9, 10, 13?
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The purpose of fermentation is to recycle what electron-transporting molecule in glycolysis?
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Identify all of the following three forms of reproductive barriers that are postzygotic barriers: 1) Gametic isolation; 2) Temporal isolation; 3) Hybrid breakdown.
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Scientists at SLAC National Accelerator Lab are studying single-atom catalysts. A catalyst can be defined as a substance that lowers what type of energy on a reaction coordinate?
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Scientists at Los Alamos National Lab are generating radioactive radium for cancer therapy. Given that radium concentrates in hydroxyapatite, what type of tumor will radium be most useful for treating? W) Liver cancers X) Brain metastases Y) Thyroid cancers Z) Bone metastases
W: W) Liver cancers
X: X) Brain metastases
Y: Y) Thyroid cancers
Z: Z) Bone metastases
Answer: Z) Z) Bone metastases
Which of the following changes is most directly responsible for the formation of rock melt at mid-ocean spreading ridges? W) Increase in temperature X) Increase in pressure Y) Decrease in temperature Z) Decrease in pressure
W: W) Increase in temperature
X: X) Increase in pressure
Y: Y) Decrease in temperature
Z: Z) Decrease in pressure
Answer: Z) Z) Decrease in pressure
Place the following three events in the formation of a caldera in chronological order: 1) Roof collapse; 2) Eruption; 3) Magma intrusion.
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The single scutellum found in corn kernels is analogous to what structure found in pairs in eudicot seeds?
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Identify all of the following three examples of symbiosis that are correctly matched with the type of symbiosis they demonstrate: 1) Pig and tapeworm with commensalism; 2) Oxpecker and cattle with mutualism; 3) Ant and aphid with parasitism.
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A thick ring of metal is heated and undergoes thermal expansion. Which of the following describes the changes that will occur to the inner and outer radii of the ring? W) Both increase X) Inner decreases, outer increases Y) Inner stays the same, outer increases Z) Inner decreases, outer stays the same
W: W) Both increase
X: X) Inner decreases, outer increases
Y: Y) Inner stays the same, outer increases
Z: Z) Inner decreases, outer stays the same
Answer: W) W) Both increase
Which of the following uniform copper objects would have the highest moment of inertia when rotated about its central axis? W) A solid cylinder with radius ten inches and length twenty inches X) A hollow cylinder with outer radius ten inches, inner radius five inches, and length twenty inches Y) A solid sphere with radius ten inches Z) A hollow sphere with outer radius ten inches and inner radius five inches
W: W) A solid cylinder with radius ten inches and length twenty inches
X: X) A hollow cylinder with outer radius ten inches, inner radius five inches, and length twenty inches
Y: Y) A solid sphere with radius ten inches
Z: Z) A hollow sphere with outer radius ten inches and inner radius five inches
Answer: W) W) A solid cylinder with radius ten inches and length twenty inches
What additional piece of information can be used in conjunction with an elemental analysis to determine the chemical formula of an unknown pure substance? W) The chemical formula can be directly calculated from the elemental analysis X) The nuclear magnetic resonance spectrum Y) The retention time on a chromatography column Z) The mass via mass spectrometry
W: W) The chemical formula can be directly calculated from the elemental analysis
X: X) The nuclear magnetic resonance spectrum
Y: Y) The retention time on a chromatography column
Z: Z) The mass via mass spectrometry
Answer: Z) Z) The mass via mass spectrometry
Identify all of the following four compounds that would cause a precipitate to form when added to a solution of 0.1-molar potassium iodide: 1) Silver nitrate; 2) Calcium chloride; 3) Lead acetate; 4) Barium nitrate.
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Acetylene and hydrogen gas form in Titan’s upper atmosphere primarily from the reactions of what molecule with ultraviolet light?
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Most of the helium in the universe was created in which of the following? W) The Big Bang X) Supernovas Y) Proton-proton chain in low-mass stars Z) CNO cycle in high-mass stars
W: W) The Big Bang
X: X) Supernovas
Y: Y) Proton-proton chain in low-mass stars
Z: Z) CNO cycle in high-mass stars
Answer: W) W) The Big Bang
What is the limit as x approaches 7 of the function with numerator 7 – x and denominator x² – 49?
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What is the quadratic polynomial with integer coefficients and smallest positive leading coefficient that has the same sum and product of all its complex zeroes as $3x^3 + 8x^2 - 5x - 2$?
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Fermilab scientists recently reported a methodology to computationally model the interactions between fermions and bosons. Identify all of the following three particles that are fermions: 1) Electron; 2) Photon; 3) Up quark.
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Scientists at Jefferson Lab recently reported observing a parity violation in an electron scattering experiment. Parity is a type of symmetry that describes the behavior of the laws of physics in which of the following situations? W) Observing a system from many different angles X) Observing a system forward and backward in time Y) Observing a system composed of matter versus a system composed of antimatter Z) Observing a system and its mirror image
W: W) Observing a system from many different angles
X: X) Observing a system forward and backward in time
Y: Y) Observing a system composed of matter versus a system composed of antimatter
Z: Z) Observing a system and its mirror image
Answer: Z) Z) Observing a system and its mirror image
What widespread feature in the rock record represents a gap of up to several hundred million years in the rock record between the Proterozoic and the Cambrian?
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In the transport of sediment, what component of the sediment load moves by saltation? W) Suspended load X) Bed load Y) Dissolved load Z) Floating load
W: W) Suspended load
X: X) Bed load
Y: Y) Dissolved load
Z: Z) Floating load
Answer: X) X) Bed load
In the standard zinc dry cell, the positive electrode is primarily composed of what element?
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Which of the following ions has the LARGEST radius? W) Rb⁺ X) In³⁺ Y) As³⁻ Z) Br⁻
W: W) Rb⁺
X: X) In³⁺
Y: Y) As³⁻
Z: Z) Br⁻
Answer: Y) Y) As³⁻
For laser light passed through a diffraction grating, doubling both the wavelength of light and the spacing of the grating will multiply the peak-to-peak separation in the diffraction pattern by what factor?
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Consider a perfectly-reflecting mirror being irradiated with light of intensity 300,000 W/m² at normal incidence. Giving your answer in pascals, what is the radiation pressure on the mirror due to this light?
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What is the antilog base 4 of 3?
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What is the cross product of vectors $\mathbf{j} + 2\mathbf{k}$ cross $2\mathbf{i} - \mathbf{j} + 4\mathbf{k}$?
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In skeletal muscle, what ion binds to troponin to allow actin to bind to myosin?
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Whales and dolphins are most closely related to which of the following groups of mammals? W) Carnivora X) Manatees Y) Even-toed ungulates Z) Odd-toed ungulates
W: W) Carnivora
X: X) Manatees
Y: Y) Even-toed ungulates
Z: Z) Odd-toed ungulates
Answer: Y) Y) Even-toed ungulates