HS Sample Set 13, Round 17 from NSB
Which of the following stars has a positive apparent magnitude? W) Polaris X) Sirius Y) Canopus Z) The Sun
W: W) Polaris
X: X) Sirius
Y: Y) Canopus
Z: Z) The Sun
Answer: W) W) Polaris
Which of the following assumptions is typically made when performing potassium-argon dating? W) Potassium-40 only decays into argon-40 X) Some percentage of argon-40 produced by decay leaks out of the rock Y) Potassium-40 has a half-life of 1.3 million years Z) All argon-40 in a rock was produced by potassium-40 decay
W: W) Potassium-40 only decays into argon-40
X: X) Some percentage of argon-40 produced by decay leaks out of the rock
Y: Y) Potassium-40 has a half-life of 1.3 million years
Z: Z) All argon-40 in a rock was produced by potassium-40 decay
Answer: Z) Z) All argon-40 in a rock was produced by potassium-40 decay
A set of test scores is normally distributed with mean 62 and standard deviation 8. What score corresponds to a Z-score of –1.25?
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What is the sum of the squares of the first 19 positive integers?
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Rank the following three atoms in terms of increasing atomic radius: 1) Argon; 2) Fluorine; 3) Lithium.
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Grignard reagents are generally made in ether-based solvents due to the instability of the metal-organic species. Identify all of the following three solvents that are considered ethereal: 1) Dioxane; 2) Tetrahydrofuran; 3) Dichloromethane.
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An electron is moving along the x-axis in the positive direction, within a uniform magnetic field that is oriented toward the positive z-axis. In which of the following directions does the Lorentz force act? W) Positive y-axis X) Negative y-axis Y) Positive z-axis Z) Negative z-axis
W: W) Positive y-axis
X: X) Negative y-axis
Y: Y) Positive z-axis
Z: Z) Negative z-axis
Answer: W) W) Positive y-axis
A hollow pipe closed at both ends has a fundamental frequency of 100 hertz. In meters, what is the length of the pipe?
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What iron-containing proteins are the main enzymes associated with the metabolism of drugs and toxins in the liver?
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Which of the following amino acids is typically phosphorylated by protein kinase A? W) Tyrosine X) Serine Y) Tryptophan Z) Isoleucine
W: W) Tyrosine
X: X) Serine
Y: Y) Tryptophan
Z: Z) Isoleucine
Answer: X) X) Serine
Oak Ridge National Lab is contributing to the production of cancer radiation treatments by producing actinium-227, which undergoes two decay transitions to become the medically-useful isotope radium-223. What two types of decay does actinium-227 undergo to become radium-223?
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Scientists at Lawrence Berkeley National Lab have been studying crystallized biomolecules with electron microscopy. In one type of experiment, the samples are immersed in liquid nitrogen to form vitreous ice before imaging. What type of electron microscopy is this?
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Which of the following geologic phenomena led to the formation of submarine canyons? W) Bioturbation X) Tsunamis Y) Turbidity currents Z) Volcanic eruptions
W: W) Bioturbation
X: X) Tsunamis
Y: Y) Turbidity currents
Z: Z) Volcanic eruptions
Answer: Y) Y) Turbidity currents
Which of Earth’s Milankovitch cycles has a period of approximately one hundred thousand years? W) Axial tilt X) Precession Y) Eccentricity Z) Obliquity
W: W) Axial tilt
X: X) Precession
Y: Y) Eccentricity
Z: Z) Obliquity
Answer: Y) Y) Eccentricity
Which of the following hormones most directly affects the metabolic rate of the body? W) Thyroid-stimulating hormone X) Thyrotropin-releasing hormone Y) Triiodothyronine Z) Testosterone
W: W) Thyroid-stimulating hormone
X: X) Thyrotropin-releasing hormone
Y: Y) Triiodothyronine
Z: Z) Testosterone
Answer: Y) Y) Triiodothyronine
Which of the following medications would likely be most effective in treating a human patient with influenza? W) Penicillin X) Ampicillin Y) Zanamivir Z) Chloroquine
W: W) Penicillin
X: X) Ampicillin
Y: Y) Zanamivir
Z: Z) Chloroquine
Answer: Y) Y) Zanamivir
Scientists at Lawrence Berkeley National Lab are developing thermoelectric materials that can convert thermal energy to electrical energy via what effect?
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Scientists at Lawrence Berkeley National Lab are part of the CUORE collaboration that is attempting to observe what ghostly leptons?
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What is the absolute value of the complex conjugate of $-6 + i$?
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$f$ is twice-differentiable with $f'(x)<0$ and $f''(x)<0$ for all real $x$. If $f(3)=22$ and $f(5)=17$, what is the largest possible integer value for $f(9)$?
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A reading of zero on what two temperature scales refers to absolute zero?
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Identify all of the following three types of imaging that depend on ionizing radiation: 1) Magnetic resonance imaging; 2) Computerized tomography; 3) Positron emission tomography.
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An aqueous-phase redox reaction has all of its stoichiometric coefficients doubled. Identify all of the following three quantities that are exactly doubled: 1) Equilibrium constant; 2) ΔG; 3) Cell potential.
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Identify all of the following three statements that are true of bonding: 1) Xenon dichloride has a bent molecular geometry; 2) Sulfur dioxide and carbon disulfide have the same molecular geometry; 3) Krypton tetrafluoride has no net dipole moment.
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In seeds, what is the term for the layer of sporophyte tissue that envelops and protects the megasporangium?
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If blood from an incompatible ABO group is mistakenly transfused, it can agglutinate. What class of antibodies mediates this process?
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If the temperature of an ideal gas is quadrupled, by what factor is the speed of sound in that gas multiplied?
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The position of a particle is given by $x(t)=t^3+4t^2+3t$. What is the acceleration at $t=5$ s, in m/s²?
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Scientists at Oak Ridge National Lab have designed a fuel rod cladding alloy made of iron, chromium, and aluminum to replace zirconium alloys. Which property must this cladding have? W) Converts fast neutrons into thermal neutrons X) Converts thermal neutrons into fast neutrons Y) Has a high neutron cross-section Z) Has a low neutron cross-section
W: W) Converts fast neutrons into thermal neutrons
X: X) Converts thermal neutrons into fast neutrons
Y: Y) Has a high neutron cross-section
Z: Z) Has a low neutron cross-section
Answer: Z) Z) Has a low neutron cross-section
Researchers at Oak Ridge National Lab have been examining how glaucoma drugs interact with a human enzyme that converts CO₂ and H₂O to bicarbonate. What is the common name of this enzyme?
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Adding ethyl-magnesium bromide to which of the following would produce a tertiary alcohol? W) A ketone X) An aldehyde Y) An alkene Z) An ether
W: W) A ketone
X: X) An aldehyde
Y: Y) An alkene
Z: Z) An ether
Answer: W) W) A ketone
Which of the following best describes how chlorine adds to an alkene? W) Both chlorine atoms add to the same carbon atom X) Chlorine atoms add with syn-stereoselectivity to adjacent carbon atoms Y) Chlorine atoms add with anti-stereoselectivity to adjacent carbon atoms Z) Only one chlorine atom adds to the carbon atoms
W: W) Both chlorine atoms add to the same carbon atom
X: X) Chlorine atoms add with syn-stereoselectivity to adjacent carbon atoms
Y: Y) Chlorine atoms add with anti-stereoselectivity to adjacent carbon atoms
Z: Z) Only one chlorine atom adds to the carbon atoms
Answer: Y) Y) Chlorine atoms add with anti-stereoselectivity to adjacent carbon atoms
If a pyramid has 8 vertices, how many edges does it have?
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What is the smallest positive zero of the function $$y=2\sin\!\Bigl(3x+\frac{3\pi}{5}\Bigr)\;?$$
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What object, as a result of tidal heating, is the most volcanically active body in the solar system?
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A galaxy is receding such that Hα appears at 657 nm instead of 656.3 nm. Which best describes the shifts in the β and γ lines? W) Both shifted longer by 0.7 nm X) Both shifted by slightly less than 0.7 nm Y) Both shifted by slightly more than 0.7 nm Z) Both shifted shorter by 0.7 nm
W: W) Both shifted longer by 0.7 nm
X: X) Both shifted by slightly less than 0.7 nm
Y: Y) Both shifted by slightly more than 0.7 nm
Z: Z) Both shifted shorter by 0.7 nm
Answer: X) X) Both shifted by slightly less than 0.7 nm
What boson mediates the strong force?
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Two identical point charges 1 m apart have potential energy 1 J. To two significant figures, what is the potential energy when four such charges occupy the corners of a 1 m square?
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In the integers mod 12, what is $7\times 11$?
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If $a,b,c$ are the zeros of $x^3-9x^2+26x-24$, what is the product $(1-a)(1-b)(1-c)$?
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What is the term for small, circular RNA molecules that can infect plants?
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Identify all of the following three types of trees that are considered gymnosperms: 1) Cycads; 2) Conifers; 3) Ginkgos.
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What functional group is formed when hot sulfuric acid is used to dehydrate an alcohol?
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Pourbaix diagrams show the most stable species in an aqueous electrolyte as a function of what two variables?
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Lapilli and cinders are subtypes of what materials that are ejected from volcanoes?
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Identify all of the following three characteristics that describe regular satellites: 1) Prograde orbit; 2) Low orbital inclination; 3) Low orbital eccentricity.
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