Periodicity Database Lab

Technetium is not a naturally occurring element, however it was predicted to exist by Mendeleev on the basis of the periodic table. Although many of its properties were predicted, it was not discovered until 1937.

In this investigation, it is assumed that the elements sulfur, calcium, and bromine were not naturally occuring elements and their properties are not available during your initial data collection.

Purpose: For two properties, examine and deduce the mathematical trends across periods and/or down groups.

Use the trends to predict the values for the proposed elements 16, 20, and 35.

Materials: Use any reputable sources for the data to be analysed. Cite sources (APA format).

Evaluation: Evaluate your predicted values using the recently published properties of these “newly discovered” elements.

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