Question

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

Answer 1

Hint: In Mendeleev’s periodic table, the elements of group 14 have a valency of 4 whereas the elements of group 13 have a valency of 3.

Complete step-by-step answer:
In Mendeleev’s periodic table, there were spaces left in the table for the unknown elements which existed with properties which are appropriate to fill the space. Mendeleev’s named them eka-boron, eka-aluminium and eka-silicon.
Eka-silicon is now known as germanium which belongs to group 14 of the periodic table. Germanium is a metalloid as they possess both metals and non-metals. The atomic number of germanium is 32 and its symbol is Ge. The valency of germanium is 4.
Eka-aluminium is now known as gallium which belongs to group 13 of the periodic table. The atomic number is 31 and it is represented by the symbol Ga. The valency of gallium is 3.
\[GeC{l_4}\] is the formula for eka-silicon chloride and \[GaC{l_3}\] is the formula for eka-aluminium chloride.
1) Chlorides of Eka-silicon – \[EC{l_4}\]
2) Chlorides of Eka-Aluminium- \[EC{l_3}\]

Therefore, the formula of chlorides of Eka-silicon and Eka-aluminium the elements predicted by Mendeleev are \[EC{l_4}\] and \[EC{l_3}\] .

Additional formula:
Eka-boron is now known as scandium which is a rare earth metal belonging to group 3. The atomic number of scandium is 21 and the symbol is Sc.

Note: Mendeleev chose the word Eka from ancient language Sanskrit that means 1. Eka-boron is named so as it lies below boron, eka-aluminium as it lies below aluminium, eka-silicon as it lies below silicon.