How many protons (p) and neutrons (n) are in an atom of barium-130?

Barium-130 is an isotope of barium, which has the atomic number 56. This means that it has 56 protons in the nucleus of its atoms.

Barium-130 has a mass number of 130, which is the sum of the number of protons and neutrons in the nucleus of the atom. The number of neutrons in an atom of barium-130 is therefore 130 - 56 = 74 neutrons.

So, an atom of barium-130 has 56 protons and 74 neutrons in its nucleus. The total number of particles in the nucleus (protons and neutrons) is therefore 56 + 74 = 130.