Same chapter3 marksDifficulty: Medium
State two advantages of the modern periodic table over Mendeleev's table.
The Periodic Table
3 marksDifficulty: Medium
State three achievements and two defects of Mendeleev's periodic table.
Original Khojo Papers practice question — not from a past board paper.
Answer
It arranged the sixty-three elements then known in a systematic way, it left gaps for elements not yet discovered and predicted their properties accurately, and it corrected several wrong atomic masses. Its defects were that hydrogen had no proper place, that certain pairs had to be placed out of order of atomic mass, and that isotopes could not be accommodated.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Every one of these defects was removed by using atomic number instead of atomic mass.
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