1. Helium is the second most abundant gas in the universe.

2. Which of the following noble gases do not occur in the elemental state in the atmosphere?

3. Which of the following is the second most abundant noble gas in the atmosphere?

4. The main commercial source of helium is natural gas.

5. Which of the following scientists first discovered helium in the solar spectrum during a total solar eclipse?

6. What is the half-life of radon?

7. What are the decay products of radium?

8. Which of the following noble gases is not obtained via fractional distillation?

9. Which of the following statements is incorrect about noble gases?

10. What is the ratio of the molar heat at constant pressure to the molar heat at constant volume for a noble gas?

11. What is the electron gain enthalpy for noble gases?

12. What is the boiling point of Helium?

13. Which of the following noble gases is most soluble in water?

14. Which of the following noble gases can diffuse through rubber?

15. Which among the following noble gases does not form clathrates?

Boron shows diagonal relation with

Catenation property is maximum in

Which one of the following is an electrophilic reagent?

Element found from sea water is

The shape of XeF₄ is

Which one of the following is the strongest lewis acid?

Which one of the following does not form hydrogen bonding?

Main source of helium is

Which one of the following dement is liquid at normal temperature?

Which one of the following is least basic?

Which of the following is the strongest oxidising agent?

Which of the following has maximum ionisation potential?

Which oxide of nitrogen is obtained on heating ammonium nitrate at 250°C ?