$$[H^+][OH^-] = 1 \times 10$$^{-14}$$

Question 1

Which property of water is primarily responsible for the ability of plants to transport water from their roots to their leaves against gravity?

Accepted Answer

Cohesive behaviour

Question 2

Why does ice float on liquid water?

Accepted Answer

Hydrogen bonds in ice are more 'ordered,' making ice less dense than liquid water

Question 3

Which equation correctly represents the relationship between hydrogen ion and hydroxide ion concentrations in pure water at 25°C?

Accepted Answer

$$[H^+][OH^-] = 1 	imes 10$$^{-14}$$

Question 4

A solution has a hydrogen ion concentration of $$1 	imes 10$$^{-4}$$ M. What is its pH?

Accepted Answer

$$pH = 4$$

Question 5

Which of the following best explains why water is an effective solvent for ionic compounds?

Accepted Answer

Water's polarity allows it to form hydration shells around ions

Question 6

What would be the effect on the freezing temperature of water if salt is added?

Accepted Answer

The freezing temperature would decrease

Question 7

Which of the following is a consequence of water's ability to moderate temperature?

Accepted Answer

Stable climates near large bodies of water

Question 8

Which statement best describes a hydrophobic substance?

Accepted Answer

It does not have an affinity for water and contains mostly nonpolar bonds

Question 9

A buffer solution contains a weak acid and its conjugate base. What is its primary function in biological systems?

Accepted Answer

To minimize changes in concentrations of $$H^+$$ and $$OH^-$$ ions

Question 10

Which of the following is a real-world consequence of ocean acidification?

Accepted Answer

Reduced availability of carbonate ions for calcification in corals

Question 11

If the pH of a solution changes from 7 to 5, how does the hydrogen ion concentration change?

Accepted Answer

It increases by 100 times

Question 12

Which of the following best describes the role of aquaporins in cells?

Accepted Answer

They facilitate the passive movement of water across cell membranes

Question 13

Why is it important for the stomach to maintain a pH of around 2?

Accepted Answer

To activate digestive enzymes and kill harmful bacteria

Question 14

Which of the following is true about acids and bases in aqueous solutions?

Accepted Answer

Acids increase the $$H^+$$ concentration, while bases reduce it

Question 15

A protein with many polar and ionic regions is placed in water. What is most likely to happen?

Accepted Answer

The protein will dissolve due to interactions with water molecules

Question 16

Which of the following is NOT an emergent property of water that contributes to Earth's suitability for life?

Accepted Answer

High viscosity

Question 17

What happens to cells when they are placed in a hypertonic solution?

Accepted Answer

They lose water and shrink

Question 18

Which of the following best explains why oil does not mix with water?

Accepted Answer

Oil molecules are hydrophobic due to their nonpolar bonds

Question 19

Which process is responsible for the formation of carbonic acid in the ocean, contributing to ocean acidification?

Accepted Answer

Absorption of $$CO_2$$ from the atmosphere by seawater

Question 20

Which formula correctly defines pH?

Accepted Answer

$$pH = -\log [H^+]$$

Water and Life: Properties, Functions, and Biological Importance

Study Guide - Practice Questions