Q32 of 52 Page 43

Write the formulae of chlorides of Eka-silicon and Eka-aluminium, the elements predicted by Mendeleev.

GeCl4, GaCl3


‘Eka-element’ term was introduced by D. I. Mendeleev in 1871. The elements were arranged in the periodic table. But all the eka-elements were discovered later. Eka-silicon discovered in 1886 was called germanium (Ge). Eka-aluminum discovered in 1875 was called gallium (Ga). Eka-boron discovered in 1879 was called scandium. The prefix ‘eka’ means ‘beyond’ on his table.


The valency of germanium is 4 so the chemical formula of its chloride is GeCl4.


The valency of gallium is 3 so the chemical formula of its chloride is GaCl3.


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