Anomalies of Mendeleev’s Periodic Table
Some elements with similar properties were placed in different groups and those with dissimilar properties were placed in same group.
Example: Tellurium (127.6) was placed in VI group but Iodine (127.0) was placed in VII group.
Similarly elements with higher atomic weights were placed before lower atomic weights based on their properties in contradiction to his periodic law. Example 59Co27 was placed before 58.7Ni28