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 in cold climates?

Accepted Answer

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

Question 3

A student adds hydrochloric acid (HCl) to pure water. What happens to the pH and the concentration of hydrogen ions?

Accepted Answer

The concentration of $$\mathrm{H^+}$$ increases and the pH decreases.

Question 4

Which equation correctly represents the dissociation of sodium hydroxide (NaOH) in water, and what effect does it have on pH?

Accepted Answer

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

Question 5

Which emergent property of water is most directly responsible for its ability to moderate temperature in living organisms?

Accepted Answer

High specific heat

Question 6

What type of bond forms between the hydrogen atom of one water molecule and the oxygen atom of another water molecule?

Accepted Answer

Hydrogen bond

Question 7

Which of the following best describes a buffer’s function in biological systems?

Accepted Answer

Buffers maintain a consistent pH when acids or bases are added.

Question 8

A solution in which water is the solvent is called:

Accepted Answer

Aqueous solution

Question 9

Which property of water explains why sweat cools the body when it evaporates?

Accepted Answer

High heat of vaporization

Question 10

Which of the following statements about hydrophobic molecules is correct?

Accepted Answer

They are nonpolar and water 'fearing'.

Question 11

What is the charge of a solute molecule surrounded by water molecules with their oxygen atoms facing inward?

Accepted Answer

Positively charged

Question 12

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 13

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

Accepted Answer

High density of ice compared to liquid water

Question 14

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

Accepted Answer

Temperature is the average kinetic energy of molecules.

Question 15

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

Accepted Answer

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

Question 16

Which of the following best describes a homogenous solution?

Accepted Answer

All parts are equally distributed.

Question 17

Which property of water is most important for dissolving salts and ions in biological systems?

Accepted Answer

Universal solvent property due to polarity

Question 18

In a neutral solution, the concentration of $$\mathrm{H^+} is$$:

Accepted Answer

Equal to the concentration of $$\mathrm{OH^-}$$

Question 19

Which of the following best describes how buffers resist changes in pH?

Accepted Answer

By donating $$\mathrm{H^+}$$ when depleted and accepting $$\mathrm{H^+}$$ when in excess

Question 20

Which of the following is a real-life example of water’s high specific heat benefiting life?

Accepted Answer

Water stabilizes the temperature of organisms and the environment.

Water: Properties, Structure, and Its Role in Chemistry

Study Guide - Practice Questions