HS Sample Set 1, Round 16 from NSB
In which of the following wavelengths does DNA absorb the best: W) 3,900 angstroms X) 260 nanometers Y) 340 nanometers Z) 540 nanometers
W: W) 3,900 angstroms
X: X) 260 nanometers
Y: Y) 340 nanometers
Z: Z) 540 nanometers
Answer: X) X) 260 nanometers
Which of the following is closest to the diameter of a plasmodesmata: W) 2 angstroms X) 60 nanometers Y) 80 microns Z) 180 microns
W: W) 2 angstroms
X: X) 60 nanometers
Y: Y) 80 microns
Z: Z) 180 microns
Answer: X) X) 60 nanometers
Name the two different bond angles present in a molecule with octahedral geometry, such as in SF₆.
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In a titration experiment, it takes 20.0 mL of a 0.05 M Ba(OH)₂ solution to neutralize 40 mL of an HNO₃ solution to the equivalence point. Calculate the molarity of HNO₃, rounded to the second decimal place.
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By words or numbers, identify all of the following four statements that MUST be true for two objects in thermal equilibrium: 1) They both must radiate no energy in any direction 2) They must be at the same temperature 3) They both must have the same thermal expansion coefficients 4) They must have the same internal energy
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How many kilojoules of thermal energy must be lost from a 250 g block of Teflon (specific heat 1 kJ kg⁻¹ K⁻¹) to lower its temperature from 125 °C to 75 °C?
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If a point has polar coordinates \((3, \pi)\), what are its rectangular coordinates?
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The graph of the polar equation \(r = 5 − 5\cos\theta\) is a cardioid. In which two quadrants is most of the area of this cardioid?
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Which of the following is a coarse-grained igneous rock primarily containing plagioclase feldspar, amphibole, and biotite: W) Gabbro X) Basalt Y) Diorite Z) Granite
W: W) Gabbro
X: X) Basalt
Y: Y) Diorite
Z: Z) Granite
Answer: Y) Y) Diorite
Of the three basic types of magma on Earth (basaltic, andesitic, rhyolitic), which one generally has the lowest eruptive temperature?
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Which of the following is the source of alpha radiation most often used in household ionization smoke detectors: W) Americium-241 X) Uranium-238 Y) Radium-226 Z) Iron-59
W: W) Americium-241
X: X) Uranium-238
Y: Y) Radium-226
Z: Z) Iron-59
Answer: W) W) Americium-241
Calculate the heating degree day (HDD) if the day’s high temperature is 70 °F and the low is 30 °F.
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Order the following three stages from the earliest to the latest in the evolution of a G-type star of two solar masses: red giant; T-Tauri; white dwarf.
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If a star has a surface temperature of 3,000 K, a core temperature of 100 million K, and a luminosity of 2,000 × our Sun, where on an H–R diagram would it most likely be found? (Choose from upper right, upper left, lower left, lower right.)
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What reduced coenzyme donates its electrons to Complex I in the mitochondrial electron transport chain?
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In a double-reciprocal (Lineweaver–Burk) plot of Michaelis–Menten kinetics, what is the effect of a competitive inhibitor? W) Change in the vertical-axis intercept X) Change in the slope only Y) Change in the horizontal-axis intercept only Z) Change in both vertical and horizontal intercepts
W: W) Change in the vertical-axis intercept
X: X) Change in the slope only
Y: Y) Change in the horizontal-axis intercept only
Z: Z) Change in both vertical and horizontal intercepts
Answer: X) X) Change in the slope only
What is the bond order for each oxygen–oxygen bond in the ozone (O₃) molecule?
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Hydrogen gas effuses through a pinhole opening from one compartment to another about how many times as fast as nitrogen gas? W) 2.4-times X) 3.7-times Y) 5.3-times Z) 8.2-times
W: W) 2.4-times
X: X) 3.7-times
Y: Y) 5.3-times
Z: Z) 8.2-times
Answer: X) X) 3.7-times
Which of the following best describes why the optical spectrum of an atom exists as discrete lines and not as a continuous spectrum? W) Atoms have electrons with unit charge X) All atoms when excited emit light Y) All energy levels of atoms are quantized Z) All electrons have spin
W: W) Atoms have electrons with unit charge
X: X) All atoms when excited emit light
Y: Y) All energy levels of atoms are quantized
Z: Z) All electrons have spin
Answer: Y) Y) All energy levels of atoms are quantized
Which of the following best describes one of Maxwell’s equations that is a mathematical conceptualization of Faraday’s law? W) A magnetic B-field is a solenoid vector field X) An EMF induced in a conductor opposes that motion Y) Induced currents are caused by the magnetic field and oppose the flux change Z) A time-varying B-field produces an E-field
W: W) A magnetic B-field is a solenoid vector field
X: X) An EMF induced in a conductor opposes that motion
Y: Y) Induced currents are caused by the magnetic field and oppose the flux change
Z: Z) A time-varying B-field produces an E-field
Answer: Z) Z) A time-varying B-field produces an E-field
At \(x = \tfrac{2}{1 -}\), the graph of \(y = x^{3}\) is: W) Increasing and concave up X) Increasing and concave down Y) Decreasing and concave up Z) Decreasing and concave down
W: W) Increasing and concave up
X: X) Increasing and concave down
Y: Y) Decreasing and concave up
Z: Z) Decreasing and concave down
Answer: X) X) Increasing and concave down
The point (3, 2) is reflected across the graph of \(y = 6\) and then reflected across the graph of \(y = x\). What are the coordinates of the final point?
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According to the EPA, excluding fires and dust, which common air pollutant has accounted for the least nationwide emissions in the past five years? W) Volatile organic compounds X) Carbon monoxide Y) Sulfur dioxide Z) Particulate matter
W: W) Volatile organic compounds
X: X) Carbon monoxide
Y: Y) Sulfur dioxide
Z: Z) Particulate matter
Answer: Z) Z) Particulate matter
Without leap days every four years, the winter solstice would start on what month and day after 70 years?
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In what layer of Earth’s atmosphere do most meteors experience the most heating?
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Name all of the following four layers of the atmosphere where temperature typically increases with altitude: troposphere; stratosphere; mesosphere; thermosphere.
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Which of the following is LEAST likely to occur when viewed from mid-northern latitudes in August: W) Venus passing within 2° of Saturn X) Neptune at opposition Y) The Moon at apogee on the 1st and perigee on the 29th of the month Z) The Moon passing within 5° of Uranus
W: W) Venus passing within 2° of Saturn
X: X) Neptune at opposition
Y: Y) The Moon at apogee on the 1st and perigee on the 29th of the month
Z: Z) The Moon passing within 5° of Uranus
Answer: Y) Y) The Moon at apogee on the 1st and perigee on the 29th of the month
Which of the following was seen from mid-northern latitudes as a bright light in August 2008 at midnight, about halfway up the southern horizon: W) Venus X) Vega Y) Jupiter Z) Uranus
W: W) Venus
X: X) Vega
Y: Y) Jupiter
Z: Z) Uranus
Answer: Y) Y) Jupiter
What is the primary calcium-binding protein in eukaryotic cells, about 148 amino acids long, that functions often through kinases and phosphatases?
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Which of the following is the RNA complementary sequence of 5′–CCGCGA–3′? W) 5′–UCGCGG–3′ X) 5′–GGCGCU–3′ Y) 5′–GGCGCT–3′ Z) 5′–TCGCGG–3′
W: W) 5′–UCGCGG–3′
X: X) 5′–GGCGCU–3′
Y: Y) 5′–GGCGCT–3′
Z: Z) 5′–TCGCGG–3′
Answer: W) W) 5′–UCGCGG–3′
For the following three processes, predict whether the change in standard entropy (ΔS°) is positive or negative, respectively: 1) Decomposition of ammonium nitrate 2) Sublimation of dry ice 3) Condensation of gaseous iodine to liquid iodine
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Consider the equilibrium \( \text{PCl}_5(g) \leftrightarrow \text{PCl}_3(g) + \text{Cl}_2(g)\). If a 1-L flask contains 0.02 mol PCl₃ and 0.02 mol Cl₂ at equilibrium and \(K_c = 5\times10^{-2}\), how many moles of PCl₅ are present?
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During beta minus decay, what nucleon type is reduced by one?
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Which of the following is NOT true of the Hall effect: W) It can be used to measure the strength of a magnetic field X) It is a consequence of a current-carrying conductor in a magnetic field Y) It was one of the first direct indications that negative charges are what move in conductors Z) It cannot distinguish between positive and negative particles
W: W) It can be used to measure the strength of a magnetic field
X: X) It is a consequence of a current-carrying conductor in a magnetic field
Y: Y) It was one of the first direct indications that negative charges are what move in conductors
Z: Z) It cannot distinguish between positive and negative particles
Answer: Z) Z) It cannot distinguish between positive and negative particles
What are the IceCube observatory under construction at the South Pole and the ANTARES telescope off the coast of France primarily designed to detect?
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During the winter solstice in the Northern Hemisphere, which of the following northern latitudes will have a day length of approximately 10.1 hours? W) 30° X) 40° Y) 50° Z) 60°
W: W) 30°
X: X) 40°
Y: Y) 50°
Z: Z) 60°
Answer: W) W) 30°
During the past 500,000 years, how many periods of major glaciation have occurred on Earth? W) 2 X) 3 Y) 4 Z) 5
W: W) 2
X: X) 3
Y: Y) 4
Z: Z) 5
Answer: Z) Z) 5
A rising parcel of air reaches its lifting condensation level at 2,000 m with a dew point of 15 °C. At 3,000 m, the parcel’s temperature on average will be: W) 15 °C X) 10 °C Y) 6 °C Z) 3 °C
W: W) 15 °C
X: X) 10 °C
Y: Y) 6 °C
Z: Z) 3 °C
Answer: X) X) 10 °C
Of the following five functions, identify all that are NOT differentiable for all real numbers: \(|x|\); \(\cos x\); \(\tan x\); \(e^x\); the greatest integer function.
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The curve defined by \(Ax^2 + Bx + Cy^2 + Dy + E = 0\) can be an ellipse if which of the constants are positive?
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What three elements are most prominent in the carbon fusion (CNO) cycle?
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If the surface of a star is 15,000 K, at what wavelength (in nanometers) does it emit its maximum energy? Round to the nearest whole number.
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What cell type is MOST directly responsible for secreting the bone matrix in developing humans?
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What specific human bone cell is antagonistic to osteoblasts and is known to cause apoptosis of osteoblasts in vitro?
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Of the following five cycloalkanes, which one has the LEAST combined angle and torsional strain energy: cyclopropane; cyclobutane; cyclopentane; cyclohexane; cyclo-octane?
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What is the most common name for the conformation that the ring structure of cyclohexane adopts to reach a strain-free value?
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What is the name of the universal constant that relates the atomic spectra of elements to that of hydrogen?
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Assuming \(G = 6.67\times10^{-11}\,\mathrm{N\,m^2/kg^2}\), what is the gravitational attraction (in newtons) between two 10 kg spheres separated by 10 m (center to center)?
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Intestinal absorption of what vitamin is most directly dependent on intrinsic factor?
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What plant hormone is primarily responsible for apical dominance in angiosperms?
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