Which of the following is true about the freezing water ?
I. H 2 O (l) > H 2 O (s) + energy
II. Q>0
III. Molecular attractions are weakened
a. I only
b. I and II only
d. I, II, and III
ba
To determine which of the statements are true about the freezing of water, let's analyze each statement:
I. H2O (l) > H2O (s) + energy
This statement is true. When water freezes, it changes from a liquid state to a solid state, and energy is released in the process. The "+" sign in the equation implies that energy is released during the freezing process.
II. Q>0
This statement is true. "Q" represents the heat transfer, and when water freezes, heat is transferred from the water to its surroundings. Positive "Q" values indicate heat transfer from the system (water) to its surroundings during the process.
III. Molecular attractions are weakened
This statement is false. When water freezes, the molecules arrange themselves into a more organized structure, forming a crystalline lattice. In this process, the molecular attractions between water molecules become stronger, not weaker.
Therefore, the correct answer is:
b. I and II only