Question

Give the atomic mass, formula of oxide and formula of hydride of the following elements as given by Mendeleev on the basis of his prediction.
(i) Eka-boron

(ii) Eka-aluminium

(iii) Eka-silicon

Answer 1

Eka-boron:-

1. This element was predicted by Mendeleev before their discovery.
2. After discovery, the element was named as Scandium.
3. Oxide formula- ${\mathrm{Sc}}_2{\mathrm{O}}_3$.
4. Hydride formula- ${\mathrm{H}}_3\mathrm{Sc}$

Eka-aluminium:-

1. This element was predicted by Mendeleev before their discovery.
2. After discovery, the element was named as Gallium
3. Oxide formula- ${\mathrm{Ga}}_2{\mathrm{O}}_3$.
4. Hydride formula- ${\mathrm{GaH}}_3$

Eka-silicon:-

1. This element was predicted by Mendeleev before their discovery.
2. After discovery, the element was named as Germanium
3. Oxide formula- ${\mathrm{GeO}}_2$.
4. Hydride formula- ${\mathrm{GeH}}_4$

Final answer:- (i) Eka-boron: Scandium, Oxide formula is ${\mathrm{Sc}}_2{\mathrm{O}}_3$ and hydride formula is ${\mathrm{H}}_3\mathrm{Sc}$.

(ii) Eka-aluminium: Gallium, Oxide formula is ${\mathrm{Ga}}_2{\mathrm{O}}_3$ and hydride formula is ${\mathrm{GaH}}_3$.

(iii) Eka-silicon: Germanium, Oxide formula is ${\mathrm{GeO}}_2$ and hydride formula is ${\mathrm{GeH}}_4$.