Density = mass / volume
D = 1 x 10⁴ / 2
D = 5000 kg/m³ in g/cm³:
1 kg/m³ ---------------- 0.001 g/cm³
5000 kg/m³ ----------- ??
5000 x 0.001 / 1 => 5.0 g/cm³
hope this helps!
Atomic Numbers are the number of protons within the nucleus,
which is 58 here.
Atomic Number=58
Mass Number is the sum of the protons and neutrons in the nucleus,
=58+82
Mass Number=140
Periodic symbol of this isotope is entirely dependent on the number of protons, 58, which corresponds to the element Cerium, abbreviated as Ce in the periodic table.
Periodic Symbol=Ce
