Question

Given that only alpha and (negative) beta decays occur, find the total number of each kind of particle produced as curium-248 decays to lead-208

Answer 1

in alpha decay , mass number decreases by 4 and atomic number decreases by 2.

in negative beta decay, atomic number increases by 1.

so if x alpha decay and y beta decay occur,

then mass number of curium-x*4=mass number of lead

==>248-x*4=208

==>x=10

atomic number of lead=82

atomic number of curium=96

atomic number of curium-2*number of alpha decay+number of beta decay=atomic number of lead

==>96-2*x+y=82

using x=10,

y=6

so 10 alpha decay and 6 negative beta decay occur.