Does platinum lose its shine?

Q. Why does a new aluminium vessel lose shine so soon after use?

Q. Which of the following object loses its shine when exposed to air and water?

Q. Metals have lustre (shine). Give reason why some metal articles become dull and lose their shine after sometime.

Q.

Copper objects lose their shine and form green coating of

Q. An iron nail is kept in each of the following liquids. In which case would it lose its shine and appear dull?