NoteCards - Ch 3Wednesday, September 23, 20159:41 AM Chapter 31In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by A) hydrogen bonds. B) nonpolar covalent bonds. C) polar covalent bonds. D) ionic bonds. E) van der Waals interactions.2The slight negative charge at one end of one water molecule is attracted to the slight positive charge of another water molecule. What is this attraction called? A) a covalent bond B) a hydrogen bond C) an ionic bond D) a hydrophilic bond E) a van der Waals interaction3The partial negative charge in a molecule of water occurs because A) the oxygen atom acquires an additional electron. B) the electrons shared between the oxygen and hydrogen atoms spend more time around the oxygen atom nucleus than around the hydrogen atom nucleus. C) the oxygen atom has two pairs of electrons in its valence shell that are not neutralized by hydrogen atoms. D) the oxygen atom forms hybrid orbitals that distribute electrons unequally around the oxygen nucleus. E) one of the hydrogen atoms donates an electron to the oxygen atom.4Sulfur is in the same column of the periodic table as oxygen, but has electronegativity similar to carbon. Compared to water molecules, molecules of H₂S A) will ionize more readily. B) will have greater cohesion to other molecules of H₂S. C) will have a greater tendency to form hydrogen bonds with each other. D) will have a higher capacity to absorb heat for the same change in temperature. E) will not form hydrogen bonds with each other.5Water molecules are able to form hydrogen bonds with A) compounds that have polar covalent bonds. B) oils. C) oxygen gas (O₂) molecules. D) chloride ions. E) any compound that is not soluble in water.6Which of the following effects is produced by the high surface tension of water? A) Lakes don't freeze solid in winter, despite low temperatures.B) A water strider can walk across the surface of a small pond. C) Organisms resist temperature changes, although they give off heat due to chemical reactions. D) Evaporation of sweat from the skin helps to keep people from overheating. E) Water flows upward from the roots to the leaves in plants.7Which of the following takes place as an ice cube cools a drink? A) Molecular collisions in the drink increase. B) Kinetic energy in the drink decreases. C) A calorie of heat energy is transferred from the ice to the water of the drink. D) The specific heat of the water in the drink decreases. E) Evaporation of the water in the drink increases.8A dietary Calorie equals 1 kilocalorie. Which of the following statements correctly defines 1 kilocalorie? A) 1,000 calories, or the amount of heat required to raise the temperature of 1 g of water by 1,000°C B) 100 calories, or the amount of heat required to raise the temperature of 100 g of water by 1°C C) 10,000 calories, or the amount of heat required to raise the temperature of 1 kg of water by 1°F D) 1,000 calories, or the amount of heat required to raise the temperature of 1 kg of water by 1°C E) 1,000 calories, or the amount of heat required to raise the temperature of 100 g of water by 100°C9The nutritional information on a cereal box shows that one serving of a dry cereal has 200 kilocalories. If one were to burn one serving of the cereal, the amount of heat given off would be sufficient to raise the temperature of 20 kg of water how many degrees Celsius? A) 0.2°C B) 1.0°C C) 2.0°C D) 10.0°C E) 20.0°C10Liquid water's high specific heat is mainly a consequence of the A) small size of the water molecules. B) high specific heat of oxygen and hydrogen atoms. C) absorption and release of heat when hydrogen bonds break and form. D) fact that water is a poor heat conductor. E) higher density of liquid water than solid water (ice).11Which type of bond must be broken for water to vaporize? A) ionic bonds B) both hydrogen bonds and ionic bonds C) polar covalent bonds D) hydrogen bonds E) both polar covalent bonds and hydrogen bonds12Temperature usually increases when water condenses. Which behavior of water is most directly responsible for this phenomenon? A) the change in density when it condenses to form a liquid or solid B) reactions with other atmospheric compounds C) the release of heat by the formation of hydrogen bonds D) the release of heat by the breaking of hydrogen bondsE) the high surface tension of water13Why does evaporation of water from a surface cause cooling of the surface? A) The breaking of bonds between water molecules absorbs heat. B) The water molecules with the most heat energy evaporate more readily. C) The solute molecules left behind absorb heat. D) Water molecules absorb heat from the surface in order to acquire enough energy to evaporate. E) The expansion of water vapor extracts heat from the surface.14Why does ice float in liquid water? A) The high surface tension of liquid water keeps the ice on top. B) The ionic bonds between the molecules in ice prevent the ice from sinking. C) Ice always has air bubbles that keep it afloat. D) Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water. E) The crystalline lattice of ice causes it to be denser than liquid water.15Hydrophobic substances such as vegetable oil are A) nonpolar substances that repel water molecules. B) nonpolar substances that have an attraction for water molecules. C) polar substances that repel water molecules. D) polar substances that have an affinity for water. E) charged molecules that hydrogen-bond with water molecules.16One mole (mol) of glucose (molecular mass = 180 daltons) is A) 180 × 10²³ molecules of glucose. B) 1 kg of glucose dissolved in 1 L of solution. C) the largest amount of glucose that can be dissolved in 1 L of solution. D) 180 kilograms of glucose. E) both 180 grams of glucose and 6.02 × 10²³ molecules of glucose.17How many molecules of glucose (C₆H₁₂O₆ molecular mass = 180 daltons) would be present in 90 grams ofglucose? A) 90 × 10²³ B) (6.02/180) × 10²³ C) (6.02/90) × 10²³ D) (90 x 6.02) × 10²³ E) (90/180) × 6.02 × 10²³18How many molecules of glycerol (C₃H₈O₃; molecular mass = 92) would be present in 1 L of a 1 M glycerol solution? A) 1 × 10⁶ B) 14 × 6.02 × 10²³ C) 92 × 6.02 × 10²³ D) 6.02 × 10²⁶ E) 6.02 × 10²³19When an ionic compound such as sodium chloride (NaCl) is placed in water, the component atoms of theNaCl crystal dissociate into individual sodium ions