| 1 | We could use argon ion. | |
| 2 | Neon, argon, and krypton are used in lighting. | |
| 3 | Chloride minus. Isoelectronic with argon. | |
| 4 | It could be aluminum, silicone, phosphorous, sulfur, c hlorine or argon. | |
| 5 | K. Neon, argon, and krypton are obtained from fractional distillation of liquid air. |