1.

A radioactive nucleus (initial mass number A and atomic number Z) emits 3 alpha -particles and 2 positrons. The ratio of number of neutrons to that of protons in the final nucleus will be:

Answer»

`(A-Z-4)/(Z-2)`
`(A-Z-8)/(Z-4)`
`(A-Z-4)/(Z-8)`
`(A-Z-12)/(Z-4)`

Solution :`""_(Z)^(A)X overset(-3alpha)to ""_(z-6)^(A-12)Y overset(-2_(1)E^(0))to ""_(z-8)^(A-12)Z`
n=A-12-(Z-8)=A-12-Z+8
=A-Z-4
and p=Z-8
`n/p=(A-Z-4)/(Z-8)`


Discussion

No Comment Found

Related InterviewSolutions