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Study Resources (Chemistry)

18.4   Short Answer Questions 1) What is the evidence that suggests planetary systems are common in the universe? 2) Why might the presence of a giant planet be both good and bad for life on a terrestrial planet in another solar system? 3) The Kepler mission, scheduled for launch in 2009, will search.
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17.7   MasteringAstronomy Concept Quiz 1) How do we determine the conditions that existed in the very early universe? A) We work backward from current conditions to calculate what temperatures and densities must have been when the observable universe was much smaller in size. B) We look all the way to the cosmological horizon,.
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16.4   Short Answer Questions 1) How do we know that there can only be insignificant amounts of dark matter in our solar system? 2) Briefly describe two different ways of measuring the mass of a cluster of galaxies. 3) What is the difference between WIMPs and MACHOs? 4) Explain how observations of white-dwarf supernovae.
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16.2   True/False Questions 1) Dark matter in galaxies and clusters of galaxies is purely hypothetical because we have no way of detecting its presence. 2) A galaxy with a lot of dark matter would have a high mass-to-light ratio compared to the Sun. 3) If the universe is accelerating, it will expand forever. 4).
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17.4   Short Answer Questions 1) Briefly explain how Hubble's discovery of a relationship between galactic distance and redshift led to the idea of the Big Bang. 2) What do we mean by inflation, and why might it have occurred at the end of the GUT era? 3) Why is the era of nucleosynthesis.
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17.5   Questions Based on MasteringAstronomy Tutorials 1) Which of the following histories are in the correct order of occurrence? A) The Big Bang, then the expansion starts, then stars make the first elements heavier than helium, then the Sun forms. B) The Big Bang happens simultaneously with the start of the expansion of.
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15.4   Short Answer Questions 1) Explain how we can estimate that there are about 50-100 billion galaxies in the observable universe. 2) Summarize the links in the distance chain that allow us to estimate distances to the farthest reaches of the universe. 3) List at least three qualities that make an astronomical object.
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6) What did COBE satellite find regarding the smoothness of the cosmic background radiation? 7) Why weren't many elements heavier than helium produced during the nucleosynthesis era? 8) What is Olbers' paradox, and what is its resolution? 9) Briefly describe one of the three questions left unanswered by the standard Big Bang theory.
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18.6   MasteringAstronomy Concept Quiz 1) Why are fossils of early life on Earth rarer than fossils of plants and animals from the past few hundred million years? A) Early organisms lacked skeletons and other hard structures that are most likely to be fossilized. B) Life was far less abundant prior to a few.
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21) How do astronomers create three-dimensional maps of the universe? A) Through the comparison of computer models of galaxy formation with observations B) By using a galaxy's position on the sky and its redshift to determine its distance along the line of sight C) by using a galaxy's position on the sky and.
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11) Is space expanding within clusters of galaxies? A) No, because their gravity is strong enough to hold them together even while the universe as a whole expands. B) No, because the universe is not old enough yet for these objects to have begun their expansion. C) No, because expansion of the universe.
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15.5   Questions Based on MasteringAstronomy Tutorials 1) Which galaxy, as observed, has aged the most since it was born? A) A very distant galaxy B) A nearby galaxy C) The distance of a galaxy doesn't matter. 2) Molly measures a Hubble constant of 20 km/sec/million light-years. Sam measures a Hubble constant of 25 km/sec/million light-years..
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11) Which of the following is not evidence for dark matter? A) the flat rotation curves of spiral galaxies B) the broad absorption lines found in the spectra of elliptical galaxies C) X-ray observations of hot gas in galaxy clusters D) gravitational lensing around galaxy clusters E) the expansion of the universe 12) Which of the.
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17.2   True/False Questions 1) In the cosmic timeline for the universe starting at the Big Bang, we live in the Planck era. 2) The observed composition of ordinary matter in the universe–roughly 75 percent hydrogen and 25 percent helium–closely matches theoretical predictions based on the Big Bang model. 3) GUT theories predict that.
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15.7   MasteringAstronomy Concept Quiz 1) In a photo like the Hubble Deep Field (Figure 15.1 in your textbook), we see galaxies in many different stages of their lives. In general, which galaxies are seen in the earliest (youngest) stages of their lives? A) The galaxies that are farthest away B) The galaxies that.
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16.5   Questions Based on MasteringAstronomy Tutorials 1) The quantity called the "enclosed mass" M(<r) represents ALL of the mass inside radius r. If the enclosed mass M(<r) is constant with increasing radius, where is the mass? A) Distributed in the shape of a doughnut, with a hole in the center B) Impossible to.
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11) Although the entire universe may be much larger than our observable universe, we can see only within our observable universe. The "boundary" of our observable universe is called ________. A) the cosmological horizon B) the Big Bang C) the lookback time D) the Hubble Deep Field 12) Cosmological redshift is the result of ________. A).
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11) The idea of dark matter arose to explain gravitational effects observed in galaxies and clusters of galaxies. However, studies of the early universe (especially of the cosmic microwave background and of chemical abundances) also tell us something about dark matter. What do they tell us? A) They add further support.
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18.5   MasteringAstronomy Reading Quiz 1) According to fossil evidence, how far back in time did life on Earth exist? A) About 3.5 billion years or more B) About 2.0 billion years C) About 545 million years D) About 65 million years 2) Why do scientists say that evolution is a "theory"? A) Because it explains a great.
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17.1   Multiple Choice Questions 1) We have direct experimental evidence (from large particle accelerators) for the physical conditions in the universe back to about ________ after the Big Bang. A) 1 million years B) 380,000 years C) 300 years D) 3 minutes E) 10-10 seconds 2) How long after the Big Bang was the Planck time, the.
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15.6   MasteringAstronomy Reading Quiz 1) Based on the number of galaxies visible in the Hubble Deep Field (Figure 15.1 in your textbook), the estimated number of galaxies in our observable universe is about ________. A) 100 billion B) 100 million C) 50,000 D) Infinity 2) Which of the following is not one of the three major.
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11) A protogalactic cloud with very little angular momentum is more likely to form an elliptical galaxy than a spiral galaxy. 12) Galaxy collisions were more common in the past. 13) Galaxy mergers take hundreds of millions of years to complete. 14) The collision of two spiral galaxies will likely result in a.
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17.6   MasteringAstronomy Reading Quiz 1) Based on our current understanding of physics, we can understand the conditions that prevailed in the early universe as far back in time as about ________. A) one ten-billionth of a second after the Big Bang B) 380,000 years after the Big Bang C) 10-45 seconds after the Big.
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11) Give several observations supporting the idea that the high redshifts of quasars really do imply great distances. 12) How are the jets produced by radio galaxies similar to those produced by protostars? 13) How are jets thought to be produced by active galaxies? 14) How do quasars produce so much energy in.
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16.7   MasteringAstronomy Concept Quiz 1) Why do we call dark matter "dark"? A) It emits no radiation that we have been able to detect. B) It is dark brown or dark red in color. C) It blocks out the light of stars in a galaxy. D) It contains large amounts of dark-colored dust. 2) Although most.
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11) Weakly interacting particles (WIMPs) interact with other particles using gravity and the weak nuclear force. They cannot emit or absorb light. Therefore, how does the behavior of hydrogen and helium gas differ from that of WIMPs? A) Hydrogen and helium gas affects particles that we can see. B) Hydrogen and helium.
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18.2   True/False Questions 1) There is good evidence that life on Earth was thriving prior to 3.85 billion years ago. 2) The modern-day organisms that seem oldest, in an evolutionary sense, are microbes that 3) Nearly all of the oxygen in the Earth's atmosphere was originally produced by photosynthesis in the leaves of.
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18.1   Multiple Choice Questions 1) Where have scientists begun an active search for life beyond the Earth? A) the Moon B) Venus C) Mars D) Europa E) Titan 2) The only place outside of Earth for which there is irrefutable evidence for ancient, microbial life is A) the Moon. B) Mars. C) Europa. D) Titan. E) None of the above–there is no.
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6) Briefly explain the purpose of the equation 7) Briefly summarize current knowledge about the term Np in the equation 8) Briefly summarize current knowledge about the term f life in the equation 9) Why do we need new forms of technology to make it possible to journey to the nearest stars within.
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15.2   True/False Questions 1) All spiral galaxies have both a disk and spheroidal component to their stellar populations. 2) Spiral galaxies have more gas, dust, and young stars than elliptical galaxies. 3) Stars continue to form in the halo of our Galaxy today. 4) A lenticular galaxy is another name for an elongated elliptical.
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16.6   MasteringAstronomy Reading Quiz 1) Which of the following best summarizes what we mean by dark matter? A) Matter that we have identified from its gravitational effects but that we cannot see in any wavelength of light B) Matter that may inhabit dark areas of the cosmos where we see nothing at all C).
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11) Which statement below correctly describes the relationship between expansion rate and age for the universe? A) The faster the rate of expansion, the younger the age of the universe. B) The faster the rate of expansion, the older the age of the universe. C) Age is independent of the expansion rate. 12) What.
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