Oil spilled into the ocean does not easily disperse, but rather clumps into an oil slick. Which of the following explains why this occurs?
A. Oil is composed mainly of hydrophilic molecules.
B. Oil is composed mainly of nonpolar molecules.
C. Oil has no hydrogen in its molecular structure, so it can't form hydrogen bonds with water.
D. Water is hydrophobic.
E. Electrons are shared unequally between carbon and hydrogen atoms.
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Question 2) Which best describes a hydrolysis reaction?
A. Molecules are broken down into smaller ones by breaking covalent bonds within water molecules and transferring hydrogen atoms and hydroxyl groups to the smaller ones.
B. Electrically charged molecules separate into ions when they dissolve in water, and then hydrogen ions and hydroxyl groups covalently attach themselves to the oppositely charged ions.
C. Large molecules are assembled from smaller ones by breaking water into hydrogen and hydroxyl ions.
D. Dissolving a large molecule in water reduces it to its individual atoms.
E. The breaking of hydrogen bonds between any two molecules.
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Question 3) Which of the following is not true of a polar chemical bond?
A. It is covalent.
B. It is ionized.
C. It has opposite electrical charge at each end.
D. It has no net electrical charge.
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Question 4) Which is true about electrolytes?
A. They are neutral atoms.
B. They conduct electricity when dissolved in water.
C. They are found in pure water.
D. They have equal numbers of protons and electrons.
E. They are insoluble in water.
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Question 5) Molecules that have properties of both polar and nonpolar molecules are called
A. hydrophobic.
B. hydrophilic.
C. amphipathic.
D. unipolar.
E. bipolar.
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Question 6) Ions are
A. electrically neutral.
B. electrically charged.
C. formed by the gain or loss of protons from the nucleus.
D. insoluble in water.
E. nonpolar atoms.
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Question 7) Which describes a characteristic of free radicals?
A. They rapidly oxidize other atoms by removing an electron.
B. They are inert molecules that don't interact readily with other molecules.
C. They contain two electrons in the outermost orbital.
D. They have extra neutrons in their nuclei.
E. They are found in high quantities in most sports drinks.
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Question 8) When magnesium loses electrons to become an ion, what does it become?
A. a covalent molecule
B. a cation
C. an anion
D. a new element
E. a free radical
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Question 9) If a sports beverage advertises that it replaces the body's electrolytes, what does the drink contain?
A. sugars that were broken down for energy
B. ionic forms of mineral elements
C. lipids that form the membranes of cells
D. oxygen and gases used by metabolism
E. vitamins
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Question 10) Of these major ions found in the body, which one carries a negative charge?
A. Chloride
B. Sodium
C. Potassium
D. Hydrogen
E. Calcium
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