Question 1

Which property of water allows a spider to walk across the surface of a pond without sinking?

Accepted Answer

Surface tension due to hydrogen bonding

Question 2

Why does ice float in liquid water, and why is this important for aquatic life during winter?

Accepted Answer

Stable hydrogen bonds in ice keep water molecules farther apart, making ice less dense than liquid water.

Question 3

A student adds table salt (NaCl) to water. What happens at the molecular level?

Accepted Answer

Water molecules surround Na+ and Cl- ions, breaking the ionic bond and forming a hydration shell.

Question 4

Which equation correctly represents the dissociation of hydrochloric acid (HCl) in water?

Accepted Answer

$$\mathrm{HCl} \rightarrow \mathrm{H}^+ + \mathrm{Cl}^-$$

Question 5

Which of the following best describes why water has a high specific heat?

Accepted Answer

Hydrogen bonds must be broken before water molecules can move faster and increase temperature.

Question 6

A solution in which water is the solvent is called a(n):

Accepted Answer

Aqueous solution

Question 7

Which of the following is NOT an emergent property of water?

Accepted Answer

High density of ice compared to liquid water

Question 8

Which of the following effects can occur because of the high surface tension of water?

Accepted Answer

A spider can walk across the surface of a small pond.

Question 9

Which of the following defines the term evaporation?

Accepted Answer

The conversion of a liquid into a vapor.

Question 10

Which property of water helps organisms resist temperature changes, even when they give off heat due to chemical reactions?

Accepted Answer

High specific heat

Question 11

Which of the following reactions is most consistent with that of a base?

Accepted Answer

$$\mathrm{NaOH} \rightarrow \mathrm{Na}^+ + \mathrm{OH}^-$$

Question 12

In a neutral solution, the concentration of:

Accepted Answer

Hydrogen ions is equal to the concentration of hydroxide ions.

Question 13

Which of the following statements about buffers is true?

Accepted Answer

They maintain a consistent pH when acids or bases are added to them.

Question 14

Which property of water is responsible for its ability to dissolve a wide variety of substances?

Accepted Answer

Water is polar and forms hydrogen bonds with solutes.

Question 15

What happens to the pH of a solution when an acid is added?

Accepted Answer

The pH decreases.

Question 16

Which of the following best describes hydrophobic molecules?

Accepted Answer

They are nonpolar water 'fearing' molecules.

Question 17

Which equation represents the relationship between pH and hydrogen ion concentration?

Accepted Answer

$$\mathrm{pH} = -\log_{10} [\mathrm{H}^+]$$

Question 18

Which property of water allows it to moderate temperature in organisms and the environment?

Accepted Answer

High specific heat

Question 19

A buffer system in blood involves carbonic acid and bicarbonate. What is the main function of this buffer?

Accepted Answer

To resist changes in pH by accepting or donating H+ ions.

Question 20

Which of the following best describes the relationship between temperature and kinetic energy in water molecules?

Accepted Answer

As temperature increases, the average kinetic energy of water molecules increases.

Properties of Water: Structure, Behavior, and Importance in Chemistry

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