Question

Are all the cations in the periodic table are smaller in size with respect to all anions in the periodic table

Answer 1

Anions are almost always larger than cations, although there are some exceptions (i.e. fluorides of some alkali metals).
Generally we say that cation is smaller than anion in case of iso-electronic species (see the fig). If you consider ions which are not iso-electronic, the statement may not be true always. if you consider cations consisting of many shells (say 6) and if you compare them with anions consisting of less shells (say 2), in that case cations will be larger than anion.