How Johann Dobereiner tried to classify the elements
Johann Dobereiner tried to classify the elements for the first time in 1817.He took three elements with similar properties, banded them together and called them triads. Chlorine, bromine and Iodine, for example, are one of the triads that Johann Dobereiner formed. The problem with this method is that firstly, a large number of similar elements like iron manganese, nickel, cobalt, zinc and copper could not be grouped into triads. Secondly, it was possible that elements with dissimilarities could be grouped into triads. Thirdly, Dobereiner could only classify 3 triads successfully. Since he failed to arrange the known elements in the form of triads his attempt at classification was largely regarded as a failure by other chemists of the time.
Between 1829 and 1858, a number of scientists found that these types of chemical relationships extended beyond the triads. During this time fluorine was added to the halogen group. Oxygen, sulfur, selenium and tellurium were grouped into a family while nitrogen, phosphorus, arsenic, antimony, and bismuth were classified as another family.
Johann Dobereiner tried to classify the elements for the first time in 1817.He took three elements with similar properties, banded them together and called them triads. Chlorine, bromine and Iodine, for example, are one of the triads that Johann Dobereiner formed. The problem with this method is that firstly, a large number of similar elements like iron manganese, nickel, cobalt, zinc and copper could not be grouped into triads. Secondly, it was possible that elements with dissimilarities could be grouped into triads. Thirdly, Dobereiner could only classify 3 triads successfully. Since he failed to arrange the known elements in the form of triads his attempt at classification was largely regarded as a failure by other chemists of the time.
Between 1829 and 1858, a number of scientists found that these types of chemical relationships extended beyond the triads. During this time fluorine was added to the halogen group. Oxygen, sulfur, selenium and tellurium were grouped into a family while nitrogen, phosphorus, arsenic, antimony, and bismuth were classified as another family.
No comments:
Post a Comment