Multiple Choice
1. Which of the following is not a noble gas?
(a) Helium
(b) Neon
(c) Argon
(d) Krypton
Answer: (d) Krypton
2. Which of the following has the lowest boiling point?
(a) Helium
(b) Neon
(c) Argon
(d) Krypton
Answer: (a) Helium
3. Which of the following has the highest density?
(a) Helium
(b) Neon
(c) Argon
(d) Krypton
Answer: (d) Krypton
4. Which of the following is the most reactive noble gas?
(a) Helium
(b) Neon
(c) Argon
(d) Krypton
Answer: (d) Krypton
5. Which of the following is the most abundant noble gas in the atmosphere?
(a) Helium
(b) Neon
(c) Argon
(d) Krypton
Answer: (c) Argon
True/False
6. Helium is the only noble gas that is not radioactive.
Answer: True
7. Neon is used to fill balloons because it is less dense than air.
Answer: False. Helium is used to fill balloons because it is less dense than air.
8. Argon is used in incandescent light bulbs to prevent the filament from oxidizing.
Answer: True
9. Krypton is used to make lasers.
Answer: True
10. Radon is a radioactive noble gas that is used in medicine.
Answer: True
Short Answer
11. What is the atomic number of helium?
Answer: 2
12. What is the chemical symbol for neon?
Answer: Ne
13. What is the boiling point of argon at 1 atm?
Answer: -185.9°C
14. What is the density of krypton at 0°C and 1 atm?
Answer: 3.749 g/L
15. What is the name of the radioactive noble gas that is used in medicine?
Answer: Radon