(a) Name an element whose properties were predicted on the basis of its position in Mendeleev's periodic table.
(b) Name two elements whose atomic weights were corrected on the basis of their positions in Mendeleev's periodic table.
(c) How many elements were known at the time of Mendeleev's classification of elements ?
a. Gallium [Eka -Aluminium], Germanium[Eka- Silicon] and Scandium[Eka Boron]
b. Gold and Platinum
c. Only 63 elements were discovered at the time of Mendeleev’s classification of elements.