Question

I ion is known to exist but not 

F ion. Explain the reason after assigning Lewis 3



structures for both the ions.​

Answer 1

• I 3- ion exists but F 3- doesnot exist.
• When we see the lewis dot structure of both the elements below, we can see F2- has octet structure, I3- has more electrons than octet.
• Some elements can afford more electrons than octet structure.
• This is because Iodine has d orbital in its electronic configuration, where as Florine doesnot.
• Iodine accomodates its more electrons in the d orbital and forms I3- ion when needed.
• But Florine due to lack of d orbital cannot accomodate any more electrons than complete octet.