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Classification of Elements and Periodicity in Properties — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryClassification of Elements and Periodicity in Properties1 Mark
MCQ
The properties of $ ......... $ were predicted by Mendeleev before their isolation.
  • A
    $\ce{Co}$ and $\ce{Ni}$
  • B
    $\ce{I}$ and $\ce{Te}$
  • ✓
    $\ce{Sc, Ga}$ and $\ce{Ge}$
  • D
    $\ce{Cl, Ar}$ and $\ce{K}$
✓

Answer

Correct option: C.
$\ce{Sc, Ga}$ and $\ce{Ge}$
ev has the foresight to leave some gaps in the periodic table for $3$ elements and these elements are discovered later and included in the table.
Those three elements are :
Eka $-$ boron is presently known as scandium $\ce{(Sc)}.$
Eka $-$ silicon is presently known as germanium $\ce{(Ge)}.$
Eka $-$ aluminium is presently known as gallium $\ce{(Ga)}$.

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