What element has the symbol 'Pt'?

The story behind the answer

The symbol Pt stands for platinum. The other options map to their own symbols: Pd is palladium, Pu is plutonium, and Po is polonium. Platinum is a dense, silvery-white noble metal prized for its resistance to corrosion and its catalytic power—hence its major role in catalytic converters, as well as in jewelry and electronics. Its name comes from the Spanish “platina” (“little silver”), first encountered in South American alluvial deposits.

Memory tip: group the “P–” elements by their second letter—Pd (palladium), Pu (plutonium), Po (polonium)—which leaves Pt for platinum. Also remember “platinum group metals” literally centers on Pt, alongside Pd, Rh, Ir, Os, and Ru.