Answer:
Neutrons = 11
Explanation:
To get the number of neurons an element has you have to subtract the number of protons from the atomic mass of that element.
The number of protons is equal to the atomic number of that element.
Atomic number = Number of Protons
So the number of protons is 25
Neutrons = Atomic mass - Number of Protons
Neutrons = 36 - 25
Neutrons = 11
1.2 x 10^10 mm^3 is equivalent to 12.0 m^3
Helium has more protons making it heavier by one atomic mass.