Answer:
4. 60 neutrons.
Explanation:
The given isotopes;
¹⁰⁶₄₆Pd
In this isotope, we can deduce that the mass number is the superscript and the atomic number is the subscript;
Mass number = 106
Atomic number = 46
Mass number is the number of protons and neutrons in an atom;
Mass number = Protons + neutrons
Atomic number is the number of protons
So, Number of protons = 46
Number of neutrons = Mass number - Atomic number
= 106 - 46
= 60
Number of neutrons = 60
