Which of the following metals is used in making the filament of an electric bulb?

Which of the following metals is known to pollute the air of big cities with a large number of vehicles?

Which two metals combine to form Bell metal?

Which of the following metals is central to chlorophyll, the pigment which gives green colour to leaves of plants?

Which of the following metals forms an amalgam with other metals?

Which of the following gases is responsible for discolouration of brass in air?