Notable for reaching very high oxidation states. Osmium tetroxide ( OsO4cap O s cap O sub 4 ) features Os in the +8positive 8 state and is a powerful (though toxic) oxidizing agent. 5. Emerging Applications: Photochemistry and Medicine Cancer Treatment: Cisplatin (
) are central to modern solar energy conversion and light-driven organic synthesis due to their long-lived excited states. Summary Table Key Property Common Use Extreme malleability; Relativistic color Electronics, Jewelry, Nanomedicine Silver (Ag) Highest thermal/electrical conductivity Photography (historically), Antimicrobials Palladium (Pd) Hydrogen "sponge" Hydrogenation, Catalytic converters Platinum (Pt) High melting point; Bio-compatibility Chemotherapy, Fuel cells Rhodium (Rh) Extreme corrosion resistance NOxcap N cap O sub x reduction in vehicles Chemistry of Precious Metals
Below is an overview of the fundamental chemical principles that govern these elements. 1. Electronic Structure and Relativistic Effects Notable for reaching very high oxidation states
). This means they prefer to remain in their metallic (0) state rather than forming ions. Electronic Structure and Relativistic Effects )
The chemistry of precious metals—primarily the (platinum, palladium, rhodium, ruthenium, iridium, and osmium) along with gold and silver —is defined by their remarkable resistance to corrosion, high density, and unique electronic configurations.
Most are insoluble in standard acids. Gold and platinum require Aqua Regia (a 3:1 mixture of HClcap H cap C l HNO3cap H cap N cap O sub 3 HNO3cap H cap N cap O sub 3 acts as an oxidant, while the Cl−cap C l raised to the negative power