Q: Q: Explosive eruptions associated with what can be tens of thousands of times as powerful as an atomic bomb? Read this paragraph and choose the correct option from the provided answers: An explosive eruption produces huge clouds of volcanic ash. Chunks of the volcano fly high into the atmosphere. Explosive eruptions can be tens of thousands of times as powerful as an atomic bomb ( Figure below ). Hot magma beneath the surface mixes with water. This forms gases. The gas pressure grows until it must be released. The volcano erupts in an enormous explosion. Choices: - forest fires - hurricanes - earthquakes - volcanoes A:
A: volcanoes

Q: Q: A change in one or more physical properties of matter without any change in chemical properties is called what? Read this paragraph and choose the correct option from the provided answers: A physical change is a change in one or more physical properties of matter without any change in chemical properties. In other words, matter doesn't change into a different substance in a physical change. Examples of physical change include changes in the size or shape of matter. Changes of statefor example, from solid to liquid or from liquid to gasare also physical changes. Some of the processes that cause physical changes include cutting, bending, dissolving, freezing, boiling, and melting. Four examples of physical change are pictured in the Figure below . You can learn more about physical changes and why they occur by watching the video at this URL:. Choices: - negative change - positive change - atmospheric change - physical change A:
A: physical change

Q: Q: The urea cycle, a set of biochemical reactions that produces urea from ammonium ions to prevent toxicity, occurs to some extent in the kidney, but primarily in what organ? Read this paragraph and choose the correct option from the provided answers: Urea Cycle The urea cycle is a set of biochemical reactions that produces urea from ammonium ions in order to prevent a toxic level of ammonium in the body. It occurs primarily in the liver and, to a lesser extent, in the kidney. Prior to the urea cycle, ammonium ions are produced from the breakdown of amino acids. In these reactions, an amine group, or ammonium ion, from the amino acid is exchanged with a keto group on another molecule. This transamination event creates a molecule that is necessary for the Krebs cycle and an ammonium ion that enters into the urea cycle to be eliminated. In the urea cycle, ammonium is combined with CO2, resulting in urea and water. The urea is eliminated through the kidneys in the urine (Figure 24.18). Choices: - spleen - skin - colon - liver A:
A: liver

Q: Q: Fusion is another nuclear process that can be used to produce energy. in this process, smaller nuclei are combined to make larger nuclei, with an accompanying release of this? Read this paragraph and choose the correct option from the provided answers: Note The first controlled chain reaction was achieved on December 2, 1942, in an experiment supervised by Enrico Fermi in a laboratory underneath the football stadium at the University of Chicago. Although fairly simple in theory, an atomic bomb is difficult to produce, in part because uranium-235, the isotope that undergoes fission, makes up only 0.7% of natural uranium; the rest is mostly uranium-238, which does not undergo fission. (Remember that the radioactive process that a nucleus undergoes is characteristic of the isotope. ) To make uranium useful for nuclear reactors, the uranium in uranium-235 must be enriched to about 3%. Enrichment of uranium is a laborious and costly series of physical and chemical separations. To be useful in an atomic bomb, the uranium in uranium-235 must be enriched to 70% or more. At lesser concentrations, the chain reaction cannot sustain itself, so no explosion is produced. Fusion is another nuclear process that can be used to produce energy. In this process, smaller nuclei are combined to make larger nuclei, with an accompanying release of energy. One example is the hydrogen fusion, which makes helium. While the steps of the process are complicated, the net reaction is: 41H 4He + 2.58 1012 J Saylor URL: http://www. saylor. org/books. Choices: - food - mineral - cells - energy A:
A: energy