What evidence indicates that the nuclei of strontium-90 atoms are unstable?

August 2018 NY Regents Chemistry Exam

27 What evidence indicates that the nuclei of strontium-90 atoms are unstable?
 

(1) Strontium-90 electrons are in the excited state.

(2) Strontium-90 electrons are in the ground state.

(3) Strontium-90 atoms spontaneously absorb beta particles.

(4) Strontium-90 atoms spontaneously emit beta particles.

Solution: Table N on the Reference Table gives decay mode for different radioisotopes. Strontium-90 has a beta decay mode.

Answer: 4

Prepare for the Chemistry Regents Exam: HERE

Contact us for chemistry tutoring: HERE

    0