The process in which metal surface is made inactive is called
passivation
galvanising
corrosion
pickling
A.
passivation
Passivation is the process in which metal surface is made inactive.
Galvanizing is the process of immersing iron or steel in a bath of molten zinc to produce a corrosion resistant, multi-layered coating of zinc-iron alloy and zinc metal.
Corrosion is a natural process that converts a refined metal into a more chemically stable form by chemical or electro-chemical reaction.
Pickling is a process of preserving or extending the lifespan of food by either anaerobic fermentation.
Which among the following alloys is used in making instruments for electrical measurements?
Stainless steel
Manganin
Spiegeleisen
Duralumin
Name the metal that is purified by placing the impure metal on sloping hearth of a reverberatory furnace and heating that above its melting point in the absence of air.
Mercury
Gallium
Zirconium
Copper
Name the reagent that is used in leaching of gold.
Carbon
Sodium cyanide
Carbon monoxide
Iodine
Name the process that is employed to refine aluminium.
Hall's process
Mond process
Hoope's process
Serperck's process
Purification of aluminium by electrolytic refining is called
Hall's process
Froth flotation process
Bayer's process
Hoop's process