Question

QUESTION 11 Rb-81 undergoes positron decay. What is the product nucleus? Enter your answer using the same format, i.e, symbol-mass number

Answer 1

The product is Kr-81 When a positron particle is decayed than the new nucleus has same in mass number and 1 unit's decreases in atomic number. To determine the product use following steps: 34Rb →?+iB The mass number of unknown product: 37 = 4+1 A = 36 The atomic number of unknown product: 81= 2-0 Z = 81 Thus the product is Kr-81 the complete reaction is as follows: 3-Rb → Kr+iB To balance the nuclear reaction following rules are following: 1. The sum of the subscript means the atomic numbers must be equal on the both side of the equation. 2. The sum of the superscript means the mass numbers must be equal on the both side of the equation. Alpha particles ( a ) decay: When an alpha particle is decayed than the new nucleus has 4 unit's decreases in mass number and 2 unit's decreases in atomic number. Beta particle (-ib) decay: When a beta particle is decayed than the new nucleus has same in mass number and 1 unit's increases in atomic number. Positron particle (B) decay: When a positron particle is decayed than the new nucleus has same in mass number and 1 unit's decreases in atomic number. Gamma ray (v) emission: This gamma ray does not affect the nuclear mass and the atomic number. It never emit independently. It emits either with alpha particle or beta particles.