Answer the following question given this paragraph: Liquids that mix with water in all proportions are usually polar substances or substances that form hydrogen bonds. For such liquids, the dipole-dipole attractions (or hydrogen bonding) of the solute molecules with the solvent molecules are at least as strong as those between molecules in the pure solute or in the pure solvent. Hence, the two kinds of molecules mix easily. Likewise, nonpolar liquids are miscible with each other because there is no appreciable difference in the strengths of solute-solute, solvent-solvent, and solute-solvent intermolecular attractions. The solubility of polar molecules in polar solvents and of nonpolar molecules in nonpolar solvents is, again, an illustration of the chemical axiom "like dissolves like. " Two liquids that do not mix to an appreciable extent are called immiscible. Layers are formed when we pour immiscible liquids into the same container. Gasoline, oil (Figure 11.15), benzene, carbon tetrachloride, some paints, and many other nonpolar liquids are immiscible with water. The attraction between the molecules of such nonpolar liquids and polar water molecules is ineffectively weak. The only strong attractions in such a mixture are between the water molecules, so they effectively squeeze out the molecules of the nonpolar liquid. The distinction between immiscibility and miscibility is really one of degrees, so that miscible liquids are of infinite mutual solubility, while liquids said to be immiscible are of very low (though not zero) mutual solubility. Q: Liquids that mix with water in all proportions are usually polar substances or substances that form these? Choices: - silicon bonds - atmospheric bonds - compressed bonds - hydrogen bonds A:
hydrogen bonds
Answer the following question given this paragraph: Q: What are the two distinct types of cells found in the animal kingdom? Choices: - DNA and Eukaryotes - bacteria and eukaryotes - chromosomes and eukaryotes - prokaryotes and eukaryotes A:
prokaryotes and eukaryotes
Q: Answer the following question given this paragraph: In a fullerene, carbon atoms are bonded to three other atoms in a soccer ball pattern. The bonds are weak, so fullerenes can dissolve and form solutions. Q: In a fullerene, what atoms are bonded to three other atoms in a soccer ball pattern? Choices: - hydrogen - oxygen - positive - carbon A:
A: carbon
Question: Answer the following question given this paragraph: Q: Toxic compounds in the environment have the most severe impact on animals that are top-level what? Choices: - vegetarian - herbivores - omnivores - carnivores A:
Answer: carnivores
*Question*
Answer the following question given this paragraph: Normal light microscopes can magnify objects up to about 1,500 times. Electron microscopes can magnify objects up to 1,000,000 times. Why can electron microscopes magnify images so much? A microscope's resolution depends on the wavelength of light used. The smaller the wavelength, the more a microscope can magnify. Light is a wave, and, as such, it has a wavelength associated with it. The wavelength of visible light, which is detected by the eyes, varies from about 700 nm to about 400 nm. One of the startling conclusions about modern science is that electrons also act as waves. However, the wavelength of electrons is much, much shorterabout 0.5 to 1 nm. This allows electron microscopes to magnify 600700 times more than light microscopes. This allows us to see even smaller features in a world that is invisible to the naked eye. Atoms act the way they do because of their structure. We already know that atoms are composed of protons, neutrons, and electrons. Protons and neutrons are located in the nucleus, and electrons orbit around the nucleus. But we need to know the structural details to understand why atoms react the way they do. Virtually everything we know about atoms ultimately comes from light. Before we can understand the composition of atoms (especially electrons), we need to understand the properties of light. Q: While normal light microscopes can magnify objects up to about 1,500 times, what advanced instruments can magnify objects up to 1,000,000 times? Choices: - magnetic microscopes - micro microscopes - electric microscopes - electron microscopes A:
**Answer**
electron microscopes
Answer the following question given this paragraph: Describe ways protists are important to humans. Q: All chemical changes involve a transfer of what? Choices: - pressure - fuel - oxygen - energy A:
energy