How do I find the radium of the sulfide ion in BeS?

The radius of Be is 59 pm. I am also given the force between them.

To find the radius of the sulfide ion in a compound such as BeS, you would typically need additional information such as the radius of the beryllium ion or the distance between the two ions. Simply knowing the force between them is not sufficient to determine the radius of the sulfide ion.

In general, to determine the ionic radius of an ion in a compound, you would need to consider the crystal structure and use techniques such as X-ray crystallography or other experimental methods. These techniques allow scientists to determine the distances between ions in a crystal lattice, which can provide information about their respective radii.

If you have additional information, such as the crystal structure and the distance between the ions, please provide those details so that I can help you further.