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? Choices: - Geiger theory - string theory - Pascal's theory - molecular orbital theory A:
molecular orbital theory
(Question)
Answer the following question given this paragraph: Ocean waves are among the most impressive waves in the world. They clearly show that waves transfer energy. In the case of ocean waves, energy is transferred through matter. But some waves, called electromagnetic waves, can transfer energy without traveling through matter. These waves can travel through space. You can read more about electromagnetic waves in the chapter "Electromagnetic Radiation. " Waves that transfer energy through matter are the focus of the present chapter. These waves are called mechanical waves. Q: What term describes waves that transfer energy through matter? Choices: - mechanical currents - temperature waves - energy currents - mechanical waves A:
(Answer)
mechanical waves
Ques: Answer the following question given this paragraph: Q: Within each sporangium, hundreds of what kind of spores develop and are dispersed through the air? Choices: - diploid - polyploid - infertile - haploid A:
Ans: haploid
(Q).
Answer the following question given this paragraph: Q: What are gymnosperms lacking compared to most angiosperms? Choices: - muscle elements - use elements - vascular elements - vessel elements A:
(A).
vessel elements
Ques:Answer the following question given this paragraph: The cell is the smallest unit of structure and function of all living organisms. Cell Biology focuses on significant aspects of the cell from its structure to its division. Some organisms contain just one cell, and others contain trillions. Some have a nucleus with DNA, others do not. Some have many organelles, others do not. But all cells are surrounded by a cell membrane. And it is this semipermeable membrane that determines what can enter and leave the cell. All cells need energy, and for many organisms, this energy comes from photosynthesis and cellular respiration. All cells come from preexisting cells through the process of cell division, which can produce a new prokaryotic organism. The cell cycle, which includes mitosis, defines the life of an eukaryotic cell. Q: The smallest unit of structure and function in all living organisms is what? Choices: - mineral - compound - particle - cell A:

Ans:cell
Answer the following question given this paragraph: Making these healthy lifestyle choices can also help prevent some types of cancer. In addition, you can lower the risk of cancer by avoiding carcinogens , which are substances that cause cancer. For example, you can reduce your risk of lung cancer by not smoking. You can reduce your risk of skin cancer by using sunscreen. How to choose a sunscreen that offers the most protection is explained below ( Figure below ). Some people think that tanning beds are a safe way to get a tan. This is a myth. Tanning beds expose the skin to UV radiation. Any exposure to UV radiation increases the risk of skin cancer. It doesn't matter whether the radiation comes from tanning lamps or the sun. Q: Avoiding carcinogens helps lower the risk of what? Choices: - radiation - colds and flu - sunburn - cancer A:
cancer