Question

when thermal energy is added to a substance, what typically happens to its particle motion?
the particles slow down and move closer together.
the particles stop moving completely.
the particles move faster and have more kinetic energy.
the particle motion remains unchanged.
what happens to water molecules during the freezing process?
they gain energy and move faster.
they lose energy and form a more organized crystal structure.
they remain at the same energy level.
they completely stop moving.

Explanation:

First Question (Thermal Energy and Particle Motion)

When thermal energy is added, particles gain kinetic energy. Kinetic energy relates to motion speed, so more thermal energy means faster particle movement and higher kinetic energy. Option 1: Slowing down is incorrect (energy added increases motion). Option 2: Stopping is wrong (particles never stop completely at non - absolute zero). Option 3: Faster movement with more kinetic energy matches. Option 4: Unchanged motion is incorrect as energy addition affects motion.

Freezing is a phase change from liquid to solid (ice). In this process, water molecules lose thermal energy. As energy decreases, their movement slows, and they form a more organized (crystalline) structure. Option 1: Gaining energy is wrong (freezing releases energy). Option 2: Same energy is incorrect (energy changes in phase change). Option 3: Losing energy and forming a crystal structure is correct. Option 4: Completely stopping is wrong (particles still vibrate in solids).

Answer:

The particles move faster and have more kinetic energy.

Second Question (Water Molecules During Freezing)