About Iridium (atomic symbol: Ir, atomic number: 77) is a Block D, Group 9, Period 6 element with an atomic weight of 192.217. The number of electrons in each of iridium's shells is [2, 8, 18, 32, 15, 2] and its electron configuration is 4f14 5d7 6s2. The iridium atom has a radius of 136 pm and a Van der Waals radius of 202 pm. Iridium was discovered and first isolated by Smithson Tennant in 1803. In its elemental form, Iridium has a silvery white appearance. Iridium is a member of theplatinum group ofmetals. It is the most corrosion resistant metal known and is the second-densest element (afterosmium). It will not react with any acid and can only be attacked by certain molten salts, such as molten sodium chloride. Iridium is found as an uncombined element and in iridium-osmium alloys. Iridium's name is derived from the Greek goddess Iris, personification of the rainbow, on account of the striking and diverse colors of its salts.

 About Ruthenium (atomic symbol: Ru, atomic number: 44) is a Block D, Group 8, Period 5 elemen with an atomic weight of 101.07. The number of electrons in each of ruthenium's shells is [2, 8, 18, 15, 1] and its electron configuration is [Kr] 4d75s1. The ruthenium atom has a radius of 134 pm and a Van der Waals radius of 207 pm. Ruthenium was discovered by J?drzej ?niadecki in 1807. It was first recognized as a distinct element by Karl Ernst Claus in 1844. In its elemental form, ruthenium has a silvery white metallic appearance. Ruthenium is a rare transition metal belonging to theplatinum group ofmetals. It is found in pentlandite, pyroxenite, and platinum group metal ores. The name Ruthenium originates from the Latin word "Ruthenia," meaning Russia.