Identify the monoatomic gas:

 For an ideal gas, which one of the following statements does not hold true?

Which of the following carbon allotropes is/are good conductor(s) of electricity?

1. Diamond
2. Graphite
3. Fullerene

Select the correct answer using the code given below :
 

Consider the following radioactive decays

I. ${}_{92}\mathrm{U}{\stackrel{-\mathrm{\alpha }}{⟶}}_{90}\mathrm{Th}$ and

II. ${}_{90}\mathrm{Th}\stackrel{-\mathrm{\alpha }}{⟶}{}_{88}\mathrm{Ra}$

In which case group of parent and daughter elements remains unchanged.

Bright light is found to emit from photographer's flashgun. This brightness is due to the presence of which one of the following noble gases?
 

In graphite, each carbon atom is bonded to three other carbon atoms forming a three-dimensional structure _____.

Which one of the following elements is a non-metal but is lustrous ?