JEE Advanced2018PhysicsNuclear PhysicsActual
In a radioactive decay chain, 90 232 Th nucleus decays to 82 212 Pb nucleus. Let N α and N β be the number of α and β - particles, respectively, emitted in this decay process. Which of the following statements is (are) true?
Options
- AN α = 5
- BN α = 6
- CN β = 2
- DN β = 4
Correct answer
A. N α = 5
Step-by-step solution
  90 232 Th is converting into   82 212 Pb Change in mass number A = 232 - 212 = 20 Mass number of an α particle = 4 ∴ No of α  particle = 20 4 = 5 Due to 5 α particle, Z will change by 10 unit. Since given change is 8 , therefore no. of β - particle is 2 .