Two characteristics of Technetium:
1) Technetium is a rare, silver-gray metal that tarnishes slowly in moist air.
2)In powder form, it burns in oxygen to form the heptoxide (Tc2O7)
Two characteristics of Tungsten:
1)Tungsten is a very hard, dense, silvery-white.
2) Tungsten is lustrous metal that tarnishes in air, forming a protective oxide coating.
