during which change of state do atoms lose energy

Daniel Parker

2 min read

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25-02-2025

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Atoms lose energy during the process of deposition. Let's explore this and other state changes to understand the energy dynamics involved.

Understanding States of Matter and Energy

Matter exists in various states: solid, liquid, gas, and plasma. These states are defined by the arrangement and energy of their atoms or molecules. Changes in state occur when energy is either added or removed from the substance.

Adding Energy: Endothermic Changes

When energy is added to a substance, its atoms or molecules gain kinetic energy – the energy of motion. This increased energy can lead to changes in state such as:

• Melting: Solid to liquid (e.g., ice melting into water). The added energy overcomes the strong intermolecular forces holding the solid together, allowing the particles to move more freely.
• Vaporization: Liquid to gas (e.g., water boiling into steam). Similar to melting, added energy breaks intermolecular forces, allowing particles to escape the liquid phase entirely. Sublimation is a special case where a solid transitions directly to a gas (e.g., dry ice).
• Ionization: Gas to plasma. Extreme energy input strips electrons from atoms, creating ions and free electrons, forming plasma.

These are all examples of endothermic changes – changes that absorb energy.

Removing Energy: Exothermic Changes

Conversely, when energy is removed from a substance, its atoms or molecules lose kinetic energy. This leads to changes in state where particles move less and become more ordered:

• Freezing: Liquid to solid (e.g., water freezing into ice). Removing energy slows down particle movement, allowing stronger intermolecular forces to hold them in a fixed structure.
• Condensation: Gas to liquid (e.g., steam condensing into water). As energy is removed, gas particles slow down enough to be held together by intermolecular forces, forming a liquid.
• Deposition: Gas to solid (e.g., frost forming on a cold surface). This is a direct transition from gas to solid, skipping the liquid phase. It requires significant energy removal to directly order the particles into a solid structure.

These are all examples of exothermic changes – changes that release energy.

Deposition: The State Change Where Atoms Lose Energy

Deposition is the only change of state where atoms directly lose energy and transition from a disordered gaseous state to an ordered solid state. In this process, the kinetic energy of gas particles decreases significantly. The particles lose enough energy to become trapped within a fixed structure, forming a solid. The released energy is transferred to the surroundings.

Think of frost forming on a windowpane on a cold winter's night. The water vapor in the air loses energy to the cold glass, causing it to directly deposit as ice crystals. This energy loss is key to the deposition process.

Conclusion

While several state changes involve energy exchange, deposition is the only one where atoms directly lose energy, resulting in a transition from a less ordered (gas) to a more ordered (solid) state. Understanding these energy dynamics is crucial to comprehending the behavior of matter under varying conditions.