Question

How can we measure the radius for noble gases?

Answer 1

Noble gases:-

• These are the elements of group 18.
• Noble gases have completely filled outermost shells, and thus are in a stable state.
• Due to this stability they don't react with other elements and hence are called noble gases.
• Some elements from this group are: Neon$\left(\mathrm{Ne}\right)$, Argon$\left(\mathrm{Ar}\right)$, Krypton$\left(\mathrm{Kr}\right)$

Measurement of radius for noble gases:-

• We already know that the noble gases have a completely filled outmost shell.
• Due to this filled electronic configuration, the inter-electronic repulsion is very high.
• As a result of this repulsion, the electrons tend to move away from each other to avoid this repulsion.
• This lead to the size of the atoms getting increased.
• The atoms in the noble gases are held together by weak Van der Waal's force.
• Hence the atomic radius for the noble gases is determined by the Van der Waals radius.
• This radius is much larger than any ionic or covalent radii.