Question

1. Answer the following questions :(Any 1)



Mendeleev predicted the existence of certain elements not known at that time. He named two of
these elements as eka - aluminium and eka - silicon.

a) Name the elements which have taken the place of these elements.

b) Mention the group and period of these elements in the modern periodic table.

c) Which one of these two elements is metalloid?

d) How many valence electrons are present in eka - silicon?

e) Eka - aluminium forms a chloride, what is its formula?​

Answer 1

Answer ❣️---

(a) Eka-silicon was replaced by Germanium and Eka-aluminium was replaced by Gallium.

(b) Gallium: Group 13 Period 5

Germanium: Group 14 period S

(c) Gallium is metal, while Germanium is metalloid

(d) Gallium has 3 valence electrons, while Germanium has 4.