Question

group displacement law define​

Answer 1

Answer:

Soddy, Fajans and Russell(1911-1913)observed that when an a-particle is lost, a new element with atomic number less by 2 and mass number less by 4 is formed. (3) When a positron is emitted, the daughter element occupies its position one group to the left of the parent element in periodic table. ..!!

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