March 23, 2017

Post a New Question

Posted by on Sunday, March 2, 2008 at 8:49pm.

What were the undiscovered elements of Mendeleev's periodic table?

  • Science - , Sunday, March 2, 2008 at 8:55pm

    He called the predicted element ekasilicon,we now know it as Ge.

  • Science - , Sunday, March 2, 2008 at 8:59pm

    Thank you for using the Jiskha Homework Help Forum. Here are some sites to visit:






  • Science - , Sunday, March 2, 2008 at 9:00pm

    Weren't there more then one?

  • Science - , Sunday, March 2, 2008 at 9:21pm

    eka-boron now Al
    eka Si now Ge
    eka Al now Ga
    I understand there were two others but I've been unable to find them. I think one MAY have been Tc, element #43.

  • Science - , Sunday, March 2, 2008 at 10:19pm

    OK. I found it.
    There were four that have been fairly widely spoken of; i.e.,
    eka Al--Ga
    eka B -- Sc
    eka Si -- Ge
    eka Mn -- Tc
    After the discovery of He and Ar, Mendeleev placed those in his chart and predicted that there should be another group 0 element lighter than He and thought that it might be responible for radioactivity. Of course that never materialized since hydrogen is the lightest element known. In addition, he suggested an element heavier than He and Ar, which he named coronium (from the sun) since he observed a spectral line in the sun that had not been identified with any other element. That was later proved to be false, also. The calibration of the spectral instrument he used was not done correctly, the line was later remeasured and the new wavelength showed it to be iron, an element already known at the time. Good thing those later predictions weren't his first; otherwise, much of the popularity of his new table rested on the prediction of the new elements and their properties he would have been ridiculed instead of praised.

Answer This Question

First Name:
School Subject:

Related Questions

More Related Questions

Post a New Question