Question

What is the atomic number (Z) of the noble gas that reacts with fluorine?

• A. 54
• B. 10
• C. 18
• D. 2

Answer 1

The correct option is A 54

From given option the atomic number of the following elements is:
He - 2
Ne -10
Ar -18
Kr -36
Xe - 54
Xenon forms three binary fluorides, $Xe{F}_2,Xe{F}_4$ and $Xe{F}_6$ by the direct reaction of elements under appropriate experimental conditions. So, only Xe reacts with $F_2.$
$Xe{F}_3$, $Xe{F}_5$ are not possible.
$Xe\left(g\right)+F_2\left(g\right)\stackrel{673K,1bar}{\to }Xe{F}_2\left(s\right)$
(xenon in excess)
$Xe\left(g\right)+2F_2\left(g\right)\stackrel{873K,7bar}{\to }Xe{F}_4\left(s\right)$
(1:5 ratio)
$Xe\left(g\right)+3F_2\left(g\right)\stackrel{573K,60-70bar}{\to }-Xe{F}_6\left(s\right)$
(1:20 ratio)
Hence, option (a) is the correct answer.