Question

Which among the following elements is not lustrous?
A. Copper
B. Gold
C. Iron
D. Iodine
E. None of these

Answer 1

Hint: Few chemical elements which are going to have a property to shine when a light is going to fall on it. The property of the chemical elements to exhibit the shining nature is called lustrous. The pure form of the metals are good examples for the lustrous nature.

Complete answer:
- In the question it is asked to find the chemical element which is not lustrous among the given options.
- Coming to the given options, option A. Copper.
- We know that all the pure metals are going to exhibit the property of shining when a light is going to fall on it.
- Therefore, the copper element is going to have the property of lustrous.
- Coming to the options B, C, and D, the chemical elements are Gold, Iron, and iodine.
- All the elements are pure metals and they are going to exhibit the property of the lustrous.

Therefore, the correct option is E, None of these.

Note:
The metals are going to exhibit the property of the luster due to the presence of the free electrons in their valence shell. When some amount of energy in the form of light is going to fall on the surface of the metals the outermost electrons excite and reach to its original state by liberating some energy in the form of light. The emitted light is nothing but the shining nature of the metals.