Rock salt is an ore of one of the following metals. This metal is: (a) Mn (b) Na (c) Fe (d) Cu
Which of the following is an ore of mercury metal? (a) rock salt (b) cinnabar (c) duralumin (d) zinc amalgam
Which of the following metals evolves hydrogen on reacting with cold dilute HNO3?
The transition metal present in vitamin B12 is: