Answer
(a) Neon-17 should be radioactive, as it falls below the stability belt (low n/p ratio).
(b) Calcium-45 also should be radioactive because of the same reason as (a).
(c) All Technetium isotopes are radioactive.
(d) Mercury-195 is radioactive. It has an even number of both neutrons and protons.
(e) All Curium isotopes are unstable.
Work Step by Step
(a) Neon-17 should be radioactive, as it falls below the stability belt (low n/p ratio).
(b) Calcium-45 also should be radioactive because of the same reason as (a).
(c) All Technetium isotopes are radioactive.
(d) Mercury-195 is radioactive. It has an even number of both neutrons and protons.
(e) All Curium isotopes are unstable.
