In stainless steel alloy, iron metal is mixed with

68 The major ore of aluminium is known as: 69 The two metals which are extracted by means of electrolytic reduction of their molten salts are : 71 If copper is kept exposed to damp air for a considerable time, it gets a green coating on its surface. This is due to the formation of: 72 Which of the following alloys contains mercury as one of the constituents?