3 The properties of last three p-block elements in the same group (elements in the 4th,5th and 6th rows) change soft-progressively (the insertion of d-block and f block). K Ca2+ Ga3+ Ge4+ AS5+ r/pm 133 99 62 53 47 Rb+ Sr2+ In3+ Sn4+ Sb5+ r/pm 148 113 81 71 62 Cst Ba2+ T13+ Pb4+ Bis+ r/pm 169 135 95 84 74 more obvious less obvious ③ The properties of last three p-block elements in the same group (elements in the 4th, 5th and 6th rows) change soft-progressively (the insertion of d-block and f￾block). K+ Ca2+ Ga3+ Ge4+ As5+ r/pm 133 99 62 53 47 Rb+ Sr2+ In3+ Sn4+ Sb5+ r/pm 148 113 81 71 62 Cs+ Ba2+ Tl3+ Pb4+ Bi5+ r/pm 169 135 95 84 74 more obvious less obvious