Name the metal which:
$(a)$ becomes blackish after a certain time.
$(b)$ develops a green coating on exposure to air.
$(c)$ does not corrode at all.
$(d)$ is used in making steel.
$(e)$ is non-lustrous.

(N/A) Silver: It reacts with sulfur compounds in the air to form a black layer of silver sulfide.
$(b)$ Copper: It reacts with moist carbon dioxide in the air to form a green layer of basic copper carbonate.
$(c)$ Platinum: It is a noble metal and is highly resistant to corrosion.
$(d)$ Nickel or Chromium: These are added to iron to make stainless steel.
$(e)$ Sodium: It is a soft,reactive metal that does not exhibit the typical metallic luster because it reacts rapidly with air and moisture.