Which of the following best explains why diamonds are very hard?
a. diamonds are made up of several different isotopes of carbon.
b. diamonds are made up of several different allotropes of carbon.
c. the atoms in a diamond are arranged in a rigid crystalline structure.
d. the atoms in a diamond are arranged in flat sheets that are tightly bonded.

Option (C)

Explanation: Diamond is the hardest element and it is because the carbon atoms are linked with one another by a strong covalent bond, forming an unbreakable crystalline structure. Covalent bonds are formed when atoms share electrons with each other.

According to the Mohr's hardness scale, diamond has hardness of 10, being the hardest of all. It is denoted by C and it crystallizes in the isometric system and its durability is very high.

Diamonds are found in the kimberlite pipes, where the kimberlite rocks are located at a great depth having extreme pressure condition.

Diamonds are often used in the jewelries.

Thus, the correct answer is option (C).

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

smooth muscle is composed of involuntary muscles found within the walls of organs and structures such as the esophagus, stomach, intestines, and blood vessels. those muscles push materials like food or blood through organs. unlike skeletal muscle, smooth muscle can never be under your control.