Which of the following diagrams best represents a sample of gas that has been ionized?

• A. Diagram 3: Shows only neutral atoms.
• B. Diagram 4: Shows tightly packed solid particles.
• C. Diagram 2: Shows a mixture of neutral gas molecules and ions.
• D. Diagram 1: Shows neutral gas molecules only.

Answer: (C)

Verified step by step guidance

1. Understand what ionization means: Ionization is the process where atoms or molecules gain or lose electrons, resulting in charged particles called ions.
2. Recall the physical states of matter and their particle arrangements: gases have particles far apart and moving freely, solids have tightly packed particles, and ionized gases (plasmas) contain both neutral particles and charged ions.
3. Analyze each diagram based on particle type and arrangement: Diagram 3 shows only neutral atoms, so no ionization; Diagram 4 shows tightly packed particles, indicating a solid, not a gas; Diagram 1 shows neutral gas molecules only, so no ionization; Diagram 2 shows a mixture of neutral gas molecules and ions, which matches the definition of an ionized gas.
4. Conclude that the diagram representing a sample of gas that has been ionized must show both neutral molecules and ions, which corresponds to Diagram 2.
5. Therefore, the best representation of an ionized gas sample is the diagram that includes both neutral gas molecules and ions, confirming Diagram 2 as the correct choice.