Q: The temperature at which the individual ions have enough kinetic energy to overcome the attractive forces that hold them in place is called? Read this paragraph and choose the correct option from the provided answers: The Relationship between Lattice Energies and Physical Properties The magnitude of the forces that hold an ionic substance together has a dramatic effect on many of its properties. The melting point, for example, is the temperature at which the individual ions have enough kinetic energy to overcome the attractive forces that hold them in place. At the melting point, the ions can move freely, and the substance becomes a liquid. Thus melting points vary with lattice energies for ionic substances that have similar structures. The melting points of the sodium halides (Figure 8.3 "A Plot of Melting Point versus the Identity of the Halide for the Sodium Halides"), for example, decrease smoothly from NaF to NaI, following the same trend as seen for their lattice energies (Figure 8.2 "A Plot of Lattice Energy versus the Identity of the Halide for the Lithium, Sodium, and Potassium Halides"). Similarly, the melting point of MgO is 2825C, compared with 996C for NaF, reflecting the higher lattice energies associated with higher charges on the ions. In fact, because of its high melting point, MgO is used as an electrical insulator in heating elements for electric stoves. Figure 8.3 A Plot of Melting Point versus the Identity of the Halide for the Sodium Halides. Choices: - occurring point - boiling point - last point - melting point A:
melting point
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Q: What does a hydrolase use to split molecules? Read this paragraph and choose the correct option from the provided answers: Hydrolase A hydrolase splits a molecule into two fragments by using water. The catalyzed reaction is referred to as a hydrolysis. Choices: - air - gas - momentum - water A:
water
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Q: What two layers is the skin made of? Read this paragraph and choose the correct option from the provided answers: Skin is made up of two layers, the epidermis on top and the dermis below. The tissue below the dermis is called the hypodermis, but it is not part of the skin. Choices: - respiration and dermis - layers and dermis - Blood and dermis - epidermis and dermis A:
epidermis and dermis
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Q: The colorless, odorless gas released when we breath is carbon dioxide. the harmful colorless, odorless gas released when matter is burned is what? Read this paragraph and choose the correct option from the provided answers: Carbon Dioxide: Every time you exhale, you release carbon dioxide into the air. It's an odorless, colorless gas. Carbon dioxide contributes to global climate change, but it isn't directly harmful to human health. Carbon Monoxide: Carbon monoxide is produced when matter burns. It's a colorless, odorless gas that is very harmful to human health. In fact, it can kill people in minutes. Because you can't see or smell carbon monoxide, it must be detected with an alarm. Choices: - carbon trioxide - methane - acid monoxide - carbon monoxide A:
carbon monoxide
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