Answer the following question given this paragraph: 8.5 End-of-Chapter Material Chapter Summary To ensure that you understand the material in this chapter, you should review the meanings of the following bold terms in the following summary and ask yourself how they relate to the topics in the chapter. A phase is a certain form of matter that has the same physical properties throughout. Three phases are common: the solid, the liquid, and the gas phase. What determines the phase of a substance? Generally, the strength of the intermolecular interactions determines whether a substance is a solid, liquid, or gas under any particular conditions. Covalent network bonding is a very strong form of intermolecular interaction. Diamond is one example of a substance that has this intermolecular interaction. Ionic interactions, the forces of attraction due to oppositely charged ions, are also relatively strong. Covalent bonds are another type of interaction within molecules, but if the bonds are polar covalent bonds, then the unequal sharing of electrons can cause charge imbalances within molecules that cause interactions between molecules. These molecules are described as polar, and these interactions are called dipole-dipole interactions. A certain rather strong type of dipole-dipole interaction, involving a hydrogen atom, is called hydrogen bonding. On the other hand, equal sharing of electrons forms nonpolar covalent bonds, and the interactions between different molecules is less because the molecules are nonpolar. All substances have very weak dispersion forces (also called London forces) caused by the movement of electrons within the bonds themselves. In the solid phase, intermolecular interactions are so strong that they hold the individual atoms or molecules in place. In many solids, the regular three-dimensional arrangement of particles makes a crystal. In other solids, the irregular arrangement of particles makes an amorphous solid. In liquids, the intermolecular interactions are Saylor URL: http://www. saylor. org/books. Q: What is the term for a certain form of matter that has the same physical properties throughout? Choices: - balance - wave - structure - phase A:
phase
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Answer the following question given this paragraph: A soil is a residual soil when it forms in place. Only about one third of the soils in the United States form this way. The material comes from the underlying bedrock. Residual soils form over many years since it takes a long time for solid rock to become soil. First, cracks break up the bedrock. This may happen due to ice wedging. Weathering breaks up the rock even more. Then plants, such as lichens or grasses, become established. They cause further weathering. As more time passes and more layers of material weather, the soil develops. Q: Soil that forms in place over a very long period is called what? Choices: - leakage soil - antique soil - resultant soil - residual soil A:
residual soil
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Answer the following question given this paragraph: Electrochemistry is the study of chemical processes that occur at the interface between an electron conductor, such as a wire, and a solution of electrolytes, which is often simply an ionic substance dissolved in water. Electrochemical processes involve a transfer of electrons between the wire and the solution. These reactions can be used to create electrical power, to purify metals, and to carry out a number of useful chemical transformations. Q: What processes involve a transfer of electrons between the wire and the solution? Choices: - radioactive - magnetic - thermal - electrochemical A:
electrochemical
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Answer the following question given this paragraph: Producers are organisms that produce food for themselves and other organisms. They use energy and simple inorganic molecules to make organic compounds. The stability of producers is vital to ecosystems because all organisms need organic molecules. Producers are also called autotrophs. There are two basic types of autotrophs: photoautotrophs and chemoautotrophs. Q: What is another name for producers? Choices: - plants - rotifers - allergens - autotrophs A:
autotrophs
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