What is the atomic number of Uranium

The story behind the answer

Atomic number equals the number of protons in an atom’s nucleus. Uranium atoms always have 92 protons, so its atomic number is 92. The option 235 is the mass number of a common isotope, U-235 (92 protons + 143 neutrons); 17 is chlorine’s atomic number; 167 isn’t assigned to any known element.

Because it’s Z=92, uranium is the heaviest element found in significant amounts in nature; elements beyond it (transuranium) are mostly man-made. Its isotopes U-235 and U-238 underpin nuclear power and weapons—U-235 is fissile. Memory tip: “U-ninety-two—after U, few”: uranium (92) marks the point after which few natural elements occur.