Question

The hardest mineral found on the earth is_____.
a. Talc
b. Coal
c. Diamond
d. Iron

Answer 1

Hint:
The crystal structure of this element is Octahedral and the crystal system is cubic. The formula mass of this element is 12.01h/mol and density is 3.51g/cm cube. It is an element of carbon.


Complete solution:
The structure of arrangements of atoms inside a diamond is very rigid. The element is very hard and has high thermal conductivity. The optical dispersion is also very high in a diamond. Optical dispersion refers to the ability to disperse light of different colours. The age of most of the natural diamond ranges between 1 billion to 3.5 billion years and the formation of most of the diamonds takes place at a depth between 150 and 250 Km under the earth’s mantle.

Synthetic diamonds are also called “ laboratory-grown diamonds or cultured diamonds”. Some of the important methods to make synthetic diamonds are Using high pressure and high temperature and using Chemical vapour deposition (CVD). The imitation diamonds have gemological characteristics. The example of imitation diamonds is high leaded glass and Cubic Zirconia. Diamonds have a high refractive index. Diamond is isotropic. The isotropic materials are those materials that are identical in all directions. The opposite term of isotropic is anisotropic that means the property of the material is dependent on directions.

Additional Information – The most common forms in which diamond occurs are euhedral, rounded octahedral, and twinned octahedra. The hardness of a diamond depends on factors such as purity, crystalline perfection, and orientation.


Hence, the correct answer is option C.

Note:
 According to the data, the highest natural diamond is obtained from the field of Copeton and Bingara that is located in New England. Diamond does not react with any reagent at room temperature.