Question

_________ having higher atomic weight was placed before nickel

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Answer 1

Answer:

Explanation: In Mendeleev's periodic table, the elements were arranged in the increasing order of their atomic masses. However, cobalt with atomic mass of 58.93 amu was placed before nickel having an atomic mass of 58.71 amu.

PLS MARK IT AS BRAINLIEST

Answer 2

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Cobalt was placed before nickel despite having atomic mass greater than that of nickel to maintain the periodicity in chemical properties.