Problem:OPTIONS:
- Geiger theory
- string theory
- Pascal's theory
- molecular orbital theory

Answer the following question given this paragraph: Hybridization involves only bonds, lone pairs of electrons, and single unpaired electrons (radicals). Structures that account for these features describe the correct hybridization of the atoms. However, many structures also include resonance forms. Remember that resonance forms occur when various arrangements of bonds are possible. Since the arrangement of bonds involves only the unhybridized orbitals, resonance does not influence the assignment of hybridization. For example, molecule benzene has two resonance forms (Figure 8.26). We can use either of these forms to determine that each of the carbon atoms is bonded to three other atoms with no lone pairs, so the correct hybridization is sp2. The electrons in the unhybridized p orbitals form bonds. Neither resonance structure completely describes the electrons in the bonds. They are not located in one position or the other, but in reality are delocalized throughout the ring. Valence bond theory does not easily address delocalization. Bonding in molecules with resonance forms is better described by molecular orbital theory. (See the next module. Q: Bonding in molecules with resonance forms is better described by which theory? A:
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A: molecular orbital theory

Problem:OPTIONS:
- ions and neutrons
- energy and mass
- volume and acceleration
- positive and negative

Answer the following question given this paragraph: Conservation of charge is the fourth of the five conservation laws in physics. There are two charges, positive and negative, and the conservation of electric charge indicates that the total charge in the universe remains the same. In any closed system charge can be transferred from one body to another or can move within the system but the total electric charge remains constant. Q: What are the two types of charges? A:
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A: positive and negative

Problem:OPTIONS:
- rust
- bacteria
- chlorine taste
- tooth decay

Answer the following question given this paragraph: Fluoride ion is widely used in water supplies to help prevent tooth decay. Chloride is an important component in ion balance in blood. Iodide ion is needed by the thyroid gland to make the hormone thyroxine. Q: Fluoride ion is widely used in water supplies to help prevent what? A:
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A: tooth decay

Problem:OPTIONS:
- momentum
- density
- magnetism
- weight

Answer the following question given this paragraph: The weight of an object is the force pulling the object downward. On Earth, this would be the gravitational force of the Earth on the object. On the moon, this would be the gravitational force of the moon on the object. The gravitational force of the moon is one-sixth the magnitude of the gravitational force of the Earth; the weight of the moon rock on the moon will be one-sixth the weight of the moon rock on the Earth's surface. Weight is measured in force unitsnewtonsby a calibrated spring scale as shown here. Q: What is the force pulling an object downward called? A:
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A:
weight