A silver articles generally turns black when kept in the open for a few days. `Why do silver articles turn black when kept in the open for a few days?Name the phenomenon involved.

A silver articles generally turns black when kept in the open for a few days. Name the black substance formed and give its chemical formula.

Silver articles and copper articles get a black and green coating respectively when kept for a long time in air. Mentions the reason for this and identify the chemical name of the coating in each case.

Explain what happens when (give equation) Silver articles become black after sometime

A student has been collecting silver coins and copper coins. One day he observed a black coating on silver coins and a green coating on copper coins. Which chemial phenomenon is responsible for these coatings. Write the chemical name of black and green coatings.

A solution of CuSO_4 was kept in an iron pot. After a few days the iron pot was found to have a number of holes in it. Explain the reasons in terms of reactivity. Write the equations of the reaction involved.

A thin zinc plate was kept ina glass container having CuSO_4 solution. On examining it was found that the blue colour of the solution is getting lighter. After a few days when the zinc plate was taken out of the solution, a number of small holes were noticed in it. State the reason and write chemical equation of the reaction.

The mother of Naresh collects the waste material of living beings in an open space. According to her, after a few days, micro-organisms break the waste material of living beings and turn it into fertilizers.What is this fertiizer called?

Explain why: An optical pyrometer (for measuring high temperature) calibrated for an ideal black body radiation gives too low value for the temperature of a red hot iron piece in the open, but gives a correct value for the temperature when the same piece is in the furnace.