Question 1

Which property of water allows insects such as water striders to walk on its surface without sinking?

Accepted Answer

Surface tension due to cohesion

Question 2

Why does ice float on liquid water?

Accepted Answer

Ice has a lower density because hydrogen bonds form a lattice structure that spaces molecules apart

Question 3

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

Accepted Answer

Hydrogen bonds between water molecules require significant energy to break

Question 4

A solution is made by dissolving table salt (NaCl) in water. In this scenario, which term correctly describes water?

Accepted Answer

Solvent

Question 5

Which equation correctly represents the dissociation of water into ions?

Accepted Answer

$$\mathrm{H}_2\mathrm{O} \rightarrow \mathrm{H}^+ + \mathrm{OH}^-$$

Question 6

Which of the following statements about hydrogen bonds in water is TRUE?

Accepted Answer

Hydrogen bonds are responsible for water's high surface tension

Question 7

A biologist observes that a plant can transport water from its roots to its leaves against gravity. Which property of water is most directly responsible for this phenomenon?

Accepted Answer

Cohesion and adhesion

Question 8

Which of the following best describes why water is considered a polar molecule?

Accepted Answer

The oxygen atom has a partial negative charge and the hydrogen atoms have partial positive charges

Question 9

Which emergent property of water is most important for moderating Earth's climate?

Accepted Answer

High specific heat

Question 10

A scientist adds a drop of oil to water and observes that the oil does not dissolve. Which term best describes the interaction between oil and water?

Accepted Answer

Hydrophobic interaction

Question 11

Which of the following is NOT an emergent property of water due to hydrogen bonding?

Accepted Answer

Ability to dissolve nonpolar substances

Question 12

Which of the following best explains evaporative cooling in biological systems?

Accepted Answer

Evaporation removes the most energetic water molecules, lowering temperature

Question 13

Which of the following equations correctly expresses the relationship between pH and hydrogen ion concentration?

Accepted Answer

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

Question 14

Which statement best describes the dynamic arrangement of water molecules?

Accepted Answer

Hydrogen bonds between water molecules constantly break and reform

Question 15

Which of the following is a consequence of water's ability to act as a versatile solvent?

Accepted Answer

Water can dissolve a wide range of substances, facilitating biochemical reactions in cells

Question 16

A student mixes hydrochloric acid (HCl) with water. What happens to the pH of the solution?

Accepted Answer

The pH decreases

Question 17

Which of the following best explains why water is essential for life on Earth?

Accepted Answer

Water participates in and facilitates chemical reactions necessary for life

Question 18

Which of the following is TRUE about the physical states of water under normal Earth conditions?

Accepted Answer

Water can exist as a solid, liquid, and gas

Question 19

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

Accepted Answer

Polarity and ability to form hydrogen bonds

Question 20

A buffer is added to a solution to maintain a stable pH. Which of the following best describes how a buffer works?

Accepted Answer

It absorbs excess hydrogen or hydroxide ions to minimize pH changes

Water and Life: Chemical Bonds, Properties, and Biological Importance

Study Guide - Practice Questions

Study Guide - Flashcards