The most common ion for lead has a charge of 4+. What element in the same period as lead has a larger ionic radius?

Question

The most common ion for lead has a charge of 4+. What element in the same period as lead has a larger ionic radius?

1.  hafnium
2.  rhenium
3.  thallium
4.  tungsten
5.  none of the above

Answer 1

1.  thallium

All of the others are larger than lead for the neutral atom, but for the ionic radius, only thallium (3+) is larger.