Q: Answer the following question given this paragraph: Because of the wave character of matter, the idea of well-defined orbits gives way to a model in which there is a cloud of probability, consistent with Heisenberg's uncertainty principle. Figure 30.48 shows how this applies to the ground state of hydrogen. If you try to follow the electron in some well-defined orbit using a probe that has a small enough wavelength to get some details, you will instead knock the electron out of its orbit. Each measurement of the electron's position will find it to be in a definite location somewhere near the nucleus. Repeated measurements reveal a cloud of probability like that in the figure, with each speck the location determined by a single measurement. There is not a well-defined, circular-orbit type of distribution. Nature again proves to be different on a small scale than on a macroscopic scale. Q: Because of the wave character of matter, the idea of well-defined orbits gives way to a model in which there is a cloud of what? Choices: - particles - mutation - chaos - probability A:
A: probability

Q: Answer the following question given this paragraph: Covalent Solids Covalent solids are formed by networks or chains of atoms or molecules held together by covalent bonds. A perfect single crystal of a covalent solid is therefore a single giant molecule. For example, the structure of diamond, shown in part (a) in , consists of sp3hybridized carbon atoms, each bonded to four other carbon atoms in a tetrahedral array to create a giant network. The carbon atoms form six-membered rings. Figure 12.19 The Structures of Diamond and Graphite. Q: Covalent solids are formed by networks or chains of atoms or molecules held together by what? Choices: - ionic bonds - bail bonds - gravitational bonds - covalent bonds A:
A: covalent bonds

Q: Answer the following question given this paragraph: The deeper water of a lake makes up the profundal zone. There isn't enough light for photosynthesis in this zone, so most organisms here eat dead organisms that drift down from the water above. Organisms in the profundal zone may include clams, snails, and some species of fish. Q: What do most organisms eat in the profundal zone of a lake? Choices: - fresh organisms - algae organism - fish waste - dead organisms A:
A: dead organisms

Q: Answer the following question given this paragraph: Many common electric devices, such as doorbells, contain electromagnets. If they have moving parts, they are likely to have an electric motor. An electric motor is a device that uses an electromagnet to change electrical energy to kinetic energy. Q: What do electric motors use to change electrical energy into kinetic? Choices: - resonances - generators - fans - electromagnets A:
A: electromagnets