Question

Give any two achievements of the Mendeleev’s Periodic classification.

Answer 1

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Answer 2

Answer:

Achievements of the Mendeleev’s Periodic classification:

• Element with a higher atomic mass was put before an element with a reduced atomic mass with an inverted sequence so which elements with comparable characteristics were grouped together.
• He left some gaps in the Periodic Table with some elements that were not found at the moment predicting the presence.  
• By prefixing a "Sanskrit number", 'Eka' (one) to the 'preceding element's name'.
• For example, later found scandium, gallium, and germanium have comparable characteristics to ‘Eka–boron’, ‘Eka –aluminum’, and ‘Eka –silicon’.
• Noble gasses such as helium (He), neon (Ne) and argon (Ar) were later found as they are present in the atmosphere owing to their inertness in extremely small levels.