Question

A radioactive nucleus ( element M with atomic number Z and mass number A) emits three alpha particles and two beta particles. Find the ratio of number of neutrons to number of protons in the final nucleus.

Answer 1

if it emits one alpha particle...then its atomic number decreases by 2 and mass number decreases by 4..so 3 alpha particles means...Z-6...A-12...N is same....one beta particle means...N-1..P+1...so.. 2 beta particles mean...N-2...P+2....so the final ratio =0-2:-6+2
=-2:-4
=2:4
=1:2

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