The nuclide ²¹²₈₃ Bi is capable of disintegrating by emitting either an -particle or a ⁻ -particle. Identify the correct pair of equations showing the products of these two decay modes.

Step-by-step solution

In -decay, the parent nucleus emits an -particle ( ⁴₂ He ). The mass number decreases by 4 and the atomic number decreases by 2 . ²¹²₈₃ Bi ²⁰⁸₈₁ Tl + In ⁻ -decay, the parent nucleus emits an electron ( e⁻ ) and an antineutrino ( ). The mass number remains unchanged and the atomic number increases by 1 . ²¹²₈₃ Bi ²¹²₈₄ Po + e⁻ +