McqMate
Q. |
A metal is exposed to the atmosphere for some time. It becomes coated with green carbonate. The metal must be – |
A. | silver |
B. | copper |
C. | aluminium |
D. | zinc |
Answer» B. copper | |
Explanation: Copper forms a rich variety of compounds with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. It does not react with water, but it slowly reacts with atmospheric oxygen forming a layer of brown-black copper oxide. In contrastto the oxidation of iron by wet air, this oxide layer stops the further, bulk corrosion. |
View all MCQs in
ChemistryNo comments yet