Question 1

Which property of water is primarily responsible for its ability to moderate coastal climates by absorbing heat in summer and releasing it in winter?

Accepted Answer

High specific heat capacity

Question 2

What is the main reason ice floats on liquid water?

Accepted Answer

Ice has a lower density than liquid water

Question 3

Which of the following best describes the hydrophobic effect?

Accepted Answer

Nonpolar molecules cluster together to minimize disruption of water's hydrogen-bonding network

Question 4

Which equation correctly represents the calculation of osmotic pressure ($$\pi) $$for a solution?

Accepted Answer

$$\pi = i c R T$$

Question 5

A solution of NaCl has a van’t Hoff factor ($$i) of 2. $$What does this value represent?

Accepted Answer

The number of solute particles produced per formula unit of NaCl

Question 6

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

Accepted Answer

Each water molecule can form up to four hydrogen bonds

Question 7

Which of the following molecules is LEAST likely to dissolve in water?

Accepted Answer

Carbon dioxide

Question 8

What is the biological significance of the hydrophobic effect?

Accepted Answer

It drives the formation of micelles and stabilizes protein folding

Question 9

Which of the following is a consequence of water’s high heat of vaporization for living organisms?

Accepted Answer

Evaporation of body fluids results in cooling effect

Question 10

Which of the following best explains why ionic compounds like NaCl dissolve easily in water?

Accepted Answer

Water’s polarity allows it to stabilize ions through electrostatic interactions

Question 11

Which of the following weak interactions is the strongest in biological systems?

Accepted Answer

Ionic/electrostatic interactions

Question 12

What is the effect of a hypertonic extracellular solution on a cell?

Accepted Answer

Water moves out of the cell, causing it to shrink

Question 13

Which of the following is TRUE regarding the colligative properties of water?

Accepted Answer

They depend only on the number of solute particles

Question 14

Which of the following best describes the process of proton hopping in water?

Accepted Answer

Protons transfer rapidly along a hydrogen-bond network

Question 15

Which of the following is NOT a property of water that contributes to its role as a solvent in biological systems?

Accepted Answer

Low boiling point

Question 16

Which of the following statements about hydrogen bonds is CORRECT?

Accepted Answer

Hydrogen bonds are strongest when the acceptor atom is in line with the covalent bond between donor atom and hydrogen

Question 17

Which of the following best explains why nonpolar gases like $$O_2$$ and $$N_2$$ are poorly soluble in water?

Accepted Answer

Their dissolution decreases entropy, making the process unfavorable

Question 18

Which of the following is TRUE about amphipathic compounds?

Accepted Answer

They contain both hydrophilic and hydrophobic regions

Question 19

Which of the following is a direct consequence of the clustering of nonpolar molecules in water?

Accepted Answer

Increase in entropy of water molecules

Question 20

Which thermodynamic equation describes the favorability of dissolving a solute in water?

Accepted Answer

$$\Delta G = \Delta H - T \Delta S$$

Water: Structure, Properties, and Biological Roles in Biochemistry

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