AP Biology chapter 3
Which of the following effects is produced by the hight surface tension of water?
a water strider can walk across the surface of a small pond
Liquid water's high specific heat is mainly a consequence of the
absorption and release of heat when hydrogen bonds break and form
Measurements show that the pH of a particular lake is 4.0. What is the hydroxide ion concentration of the lake?
10^-10 M
Measurements show that the pH of a particular lake is 4.0. What is the hydrogen ion concentration of the lake?
10^-4 M
How many grams would be equal to 1 mol of the compound C2H4O2? (carbon=12, oxygen=16, hydrogen=1)
60
What accounts for the movement of water up the vessels of a tree?
adhesion
Many of water's emergent properties, such as its cohesion, its high specific heat, and its high heat of vaporization, result from the fact that water molecules
are attracted to each other by partial negative and positive charges on the oxygen and hydrogen atoms, respectively
Why is water such an excellent solvent?
as a polar molecule, it can surround and dissolve ionic and polar molecules
Carbon dioxide (CO2) is readily soluble in water, according to the equation CO2+H20<->H2CO3. Carbonic acid (H2CO3) is a weak acid. Respiring cells release CO2 into the bloodstream. What will be the effected of pH of blood as that blood first comes in contact with respiring cells?
blood pH will decrease slightly
Which of the following solutions would require the greatest amount of base to be added to bring the solution to neutral pH?
gastric juice at pH 2
Because organisms are made primarily of water, they resist rapid temperature changes. This useful quality is based on water's
high specific heat
The bonds that are broken when water vaporizes are
hydrogen bonds between water molecules
Why does ice float in liquid water?
hydrogen bonds stabilize and keep the molecules of ice further apart than the water molecules of liquid water
A 0.01 M solution of a substance has a pH of 2. What can you conclude about this substance?
it is a strong acid that ionizes completely in water
Some archaea are able to live in lakes with pH values of 11. How does pH 11 compare with the ph 7 typical of your body cells?
it is ten thousand times more basic than pH 7
What is the pH of a solution with a hydroxyl ion [HO-] concentration of 10^-12 M?
pH 12
Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature?
the absorption of heat by the breaking of hydrogen bonds
If the cytoplasm of a cell is at pH 7, and the mitochondrial matrix is at pH8, this means that
the concentration of H+ ions is tenfold higher in the cytoplasm than in the mitochondria matrix
The partial negative charge in a molecule of water occurs because
the electrons shared between the oxygen and hydrogen atoms spend more time around the oxygen atom nucleus than around the hydrogen atom nucleus
Which of the following is a hydrophobic material?
wax