What was the unknown element under aluminium called?
- AOption (a)
Neo-Aluminium
- BOption (b)
Proto-Aluminium
- COption (c)
Eka-Aluminium
- DOption (d)
Meta-Aluminium
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Correct answer
Eka-Aluminium
Why this answer is correct
The correct answer is Eka-Aluminium.
Key Points
- Eka-Aluminium was the name given by Dmitri Mendeleev to the unknown element predicted to lie below aluminium in the periodic table.
- Mendeleev formulated this term based on his periodic law, where "Eka-" means "one beyond" in Sanskrit, indicating its position relative to aluminium.
- The element later discovered and identified as Eka-Aluminium is Gallium (Ga), which was found in 1875 by French chemist Paul-Émile Lecoq de Boisbaudran.
- Mendeleev accurately predicted various properties of Eka-Aluminium, including its atomic mass, density, melting point, and oxide formula.
- The discovery of Gallium validated Mendeleev’s periodic table and his concept of periodicity, strengthening the scientific acceptance of the table.
Additional Information
- Periodic Law:
- Mendeleev's periodic law states that the properties of elements are a periodic function of their atomic masses.
- This law formed the basis for the organization of elements in the periodic table.
- Gallium:
- Gallium has an atomic number of 31 and is a soft, silvery metal.
- It melts at a low temperature of about 29.76°C, making it unique among metals.
- Gallium is used in semiconductors, LEDs, and solar panels.
- Mendeleev's Predictions:
- Mendeleev predicted the existence and properties of several elements that were unknown at the time, including Scandium (Eka-Boron), Gallium (Eka-Aluminium), and Germanium (Eka-Silicon).
- His predictions were based on gaps in his periodic table.
- Validation of Periodic Table:
- The discovery of elements like Gallium, which matched Mendeleev's predictions, confirmed the accuracy and utility of the periodic table.
- This established the periodic table as one of the most important tools in chemistry.