In 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.
C
Which 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.
B
A dietary Calorie equals 1 kilocalorie. Which of the following statements correctly defines 1 kilocalorie?
A) 1000 calories or the amount of heat required to raise the temperature of 1 g of water by 1000°C B) 100 calories or the amount of heat required to raise the temperature of 100 g of water by 1°C C) 10000 calories or the amount of heat required to raise the temperature of 1 kg of water by 1°F D) 1000 calories or the amount of heat required to raise the temperature of 1 kg of water by 1°C E) 1000 calories or the amount of heat required to raise the temperature of 100 g of water by 100°C
D
Which 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 bonds
D
The four emergent properties of water that are important for life are:
A) Cohesion/ expansion upon freezing/ high heat of evaporation/ and capillarity B) Cohesion/ moderation of temperature/ expansion upon freezing/ and solvent properties C) Moderation of temperature/ solvent properties/ high surface tension/ and capillarity D) Heat of vaporization/ high specific heat/ high surface tension/ and capillarity E) Polarity/ hydrogen bonding/ high specific heat/ and high surface tension
B
Which of the following ionizes completely in solution and is considered to be a strong base (alkali)?
A) NaCl B) HCl C) NH3 D) H2CO3 E) NaOH
E
What is the pH of a solution with a hydroxyl ion [OH-] concentration of 10-12 M? A) pH 2 B) pH 4 C) pH 10 D) pH 12 E) pH 14
A
Sugar dissolves when stirred into water. The sugar is the ______ the water is the ______ and the sweetened water is the ______.
A) solution . . . solvent . . . solute B) solute . . . solvent . . . solution C) solvent . . . solute . . . solution D) solution . . . solute . . . solvent E) solvent...solution...solute
B
How would acidification of seawater affect marine organisms?
A) Acidification would increase dissolved carbonate concentrations and promote faster growth of corals and shell-building animals. B) Acidification would decrease dissolved carbonate concentrations and promote faster growth of corals and shell-building animals. C) Acidification would increase dissolved carbonate concentrations and hinder growth of corals and shell-building animals. D) Acidification would decrease dissolved carbonate concentrations and hinder growth of corals and shell-building animals. E) Acidification would increase dissolved bicarbonate concentrations and cause increased calcification of corals and shellfish.
D
Relative to a pH of 6 a pH of 4 has a ______.
A) 200 times higher H+ concentration B) 100 times higher H+ concentration C) 20 times higher H+ concentration D) 20 times lower H+ concentration E) 100 times lower H+ concentration
B