Chapter 3 Review Ap Bio

1.

Cells are surrounded by water, and cells themselves consist of about 70% to 95% water. As a result _____. The Correct Answer: the temperature of living things tends to change relatively slowly a variety of nutrient molecules are readily available as dissolved solutes waste products produced by cell metabolism can be easily removed dissolved substances can be easily transported within a cell or between cells in multicellular organisms

2.

Water is a polar molecule. This means that _____. The Correct Answer: the opposite ends of the molecule have opposite electrical charges

3.

The tendency of water molecules to stay close to each other as a result of hydrogen bonding _____. The Correct Answer: provides the surface tension that allows leaves to float on water is called cohesion keeps water moving through the vessels in a tree trunk acts to moderate temperature

4.

In a group of water molecules, hydrogen bonds form between _____. The Correct Answer: the oxygen atom in one water molecule and a hydrogen atom in another water molecule

5.

What do cohesion, surface tension, and adhesion have in common with reference to water? The Correct Answer: All are properties related to hydrogen bonding.

6.

Most of water's unique features (for example, its versatility as a solvent, ability to moderate temperature, and cohesive behavior) result from the fact that _____. The Correct Answer: oxygen attracts electrons more than hydrogen does

7.

The partial charges on a water molecule occur because of _____. The Correct Answer: the unequal sharing of electrons between the hydrogen and the oxygen atoms of a water molecule

8.

The ability of water molecules to form hydrogen bonds with other water molecules and water's ability to dissolve substances that have charges or partial charges are _____. The Correct Answer: both caused by water's partial charges

9.

The phenomenon responsible for the maintenance of a column of water as it moves upward through a vessel is _____. The Correct Answer: cohesion

10.

Adhesion is best described as _____. The Correct Answer: the clinging of one substance to another substance

11.

You can fill a glass of water to just slightly above the rim without it spilling over the glass. What property of water best explains this phenomenon? The Correct Answer: surface tension

12.

Which action would involve the greatest transfer of heat? The Correct Answer: condensing 5 g of steam to liquid water

13.

Which example is not an effect of water's high specific heat? The Correct Answer: Inland regions generally have milder climates than coastal regions.

14.

The amount of heat required to change the temperature of 1 g of any substance by 1°C is defined as _____. The Correct Answer: the specific heat of that substance

15.

The amount of heat required to convert 1 g of any substance from the liquid to the gaseous state is defined as _____. The Correct Answer: the heat of vaporization of that substance

16.

The reason that coastal climates are more moderate than inland climates is

due primarily to water's high _____. The Correct Answer: specific heat 17.

Sweating has a cooling effect because of water's high _____. The Correct Answer: heat of vaporization

18.

Water molecules have _____ than molecules of similar size, such as ammonia and methane. The Correct Answer: a higher boiling point

19.

Because molecules of water are farther apart in ice than in liquid water, _____. The Correct Answer: ice floats

20.

Water is a very versatile solvent because water molecules are_____. The Correct Answer: polar

21.

Sodium chloride (NaCl) dissolves in water because water molecules _____. The Correct Answer: are polar

22.

Nonpolar molecules that cluster away from water molecules are called _____ molecules. The Correct Answer: hydrophobic

23.

Hydrophilic substances, but not hydrophobic substances, _____. The Correct Answer: have charges and partial charges to which water molecules can adhere

24.

A molecule that has all nonpolar covalent bonds would be _____. The Correct Answer: hydrophobic

25.

Hydrophobic molecules are _____ water. The Correct Answer: repelled by

26.

Some substances, such as oil and gasoline, will not dissolve in water because _____. The Correct Answer: their molecules have no charges or partial charges to which water molecules can adhere

27.

An acid is _____. The Correct Answer: a compound that donates hydrogen ions to a solution

28.

Sucrose has a molecular mass of 342 daltons. To make a 2-molar (2 M) solution of sucrose, _____. The Correct Answer: stir 342 g of sucrose in water to dissolve the sugar, and then add enough water to bring the total volume of the solution up to 0.5 L

29.

A mole of ethyl alcohol weighs 46 g. How many grams of ethyl alcohol are needed to produce 1 L of a 2-millimolar (2 mM) solution? The Correct Answer: 0.092 g

30.

Adding acid tends to ____ of a solution. The Correct Answer: increase the hydrogen ion concentration and lower the pH

31.

Which of the following dissociations is that of an acid? The Correct Answer: HF → H+ + F-

32.

A glass of grapefruit juice, at pH 3, contains _____ H+ as a glass of tomato juice, at pH 4. The Correct Answer: ten times as much

33.

A solution at pH 6 contains ____ than the same amount of solution at pH 8. The Correct Answer: 100 times more H+

34.

Adding a base tends to _____ of a solution. The Correct Answer: lower the hydrogen ion concentration and increase the pH

35.

When the pH of a solution shifts from 7 to 3, how has the hydrogen ion concentration changed? The Correct Answer: It has increased by 10,000 times.

36.

Pure water has a pH of 7. Why does uncontaminated rainwater have a pH

of 5.6? The Correct Answer: formation of carbonic acid from carbon dioxide and water 37.

A substance that minimizes changes in the concentration of H+ and OH- in a solution is a(n) ______. The Correct Answer: buffer

38.

Which of the following statements does not correctly describe a buffer? The Correct Answer: None of the above (all the above statements correctly describe a buffer).

39.

Which of the following statements is true about acid precipitation? The Correct Answer: It washes away some minerals that are plant nutrients, while causing some toxic minerals to accumulate.