Question

question 3 (2.5 points)
when water molecules form into ice, ____.
the water molecules jiggle more
their structure becomes less rigid
the water molecules pack less densely
hydrogen bonds between water molecules readily break
evaporation of water molecules happens more readily

Explanation:

When water freezes to form ice, the hydrogen - bonded structure of water becomes more stable. In liquid water, hydrogen bonds are constantly breaking and reforming. But in ice, the hydrogen bonds hold the water molecules in a more rigid, open - lattice structure. This open structure means that water molecules in ice are less densely packed compared to liquid water.

• When water molecules form into ice, the temperature decreases. Kinetic energy is related to temperature ($KE=\frac{3}{2}kT$, where $k$ is Boltzmann's constant and $T$ is temperature). As temperature ($T$) decreases, the kinetic energy of water molecules decreases, so they jiggle less, not more.
• The structure of ice is more rigid than that of liquid water due to the stable hydrogen - bonded lattice in ice.
• In ice, the hydrogen bonds are more stable (less likely to break) compared to liquid water where hydrogen bonds are in a dynamic state of breaking and reforming.
• Evaporation is a process related to the escape of molecules from the liquid phase to the gas phase. Ice is in the solid phase, and the rate of evaporation (sublimation in the case of ice) is much lower than that of liquid water under normal conditions.

Answer:

the water molecules pack less densely