Platinum.
Platinum is a rare element too. Atomic number of platinum is 78.
The only element with 78 protons is platinum (Pt).
Platinumit has 6 naturally occurring isotopes: 190 (78 protons and 112 neu-trons), 192 (78 protons and 114 neutrons), 194 (78 protons and 116 neu-trons), 195 (78 protons and 117 neutrons), 196 (78 protons and 118 neu-trons), 198 (78 protons and 120 neutrons).
PLatinum is an element with 78 protons. Platinum is a dense, malleable, ductile, precious, gray-white transition metal. It is also called as Noble Metal. Platinum is the rarest mineral on earth also. It has 78 protons.
They are both Isotopes of Barium. The 56 protons tell us that the element is Barium and when you add the neutrons with the protons you get barium138 and barium134. They are both stable isotobes of barium but of all the barium in the world about 72% is barium138 and 2% is barium134.
The element platinum (Pt) has 78 protons in the atomic nucleus.
Caesium is a metal element. Atomic mass of it is 133.
Platinum is a non metal element. Atomic number of it is 78.
Platinum is a metal element. atomic number of it is 78.
Platinum(Pt) has 78 protons. Gold(Au) has 79 protons
Platinum is one of three precious metals. It is a metallic element with the atomic number 78 and the symbol Pt.
I think you meant "54 protons, 54 electrons, and 78 neutrons," because I don't think it's possible for any element to have such a high proton-electron different, especially when that element is the noble gas Xenon. Anyways, if you did make a typo, the element you're thinking of should be Xenon-134