Question

Assertion
Diamond and graphite are allotropes of carbon.
Reason
Some elements can have several different structural forms while in the same physical state. These different forms are called allotropes.
The above question contains an assertion followed by reason. Read them carefully and select the option that best describes the 2 statements.
A. Both assertion and reason are correct and reason is the correct explanation of assertion.
B. Both assertion and reason are correct but reason in not the correct explanation of assertion.
C. Assertion is correct but reason is incorrect.
D. Assertion is incorrect but reason is correct.

Answer 1

The property of the chemical element to exist in more than two forms is called allotropy. In allotropism the same element is available in different forms in molecular level but has different physical properties.

Complete step by step answer:
Allotropy is defined as the property of a chemical compound to exist in several structural forms and differ in the arrangement of the atoms in the molecule. The elements which exist in two or more than two forms are known as allotropes.
The allotropes are carbon atoms are graphite and diamond. Both the allotropes of carbon are present in the same physical state that is in solid form. In graphite, carbon atoms are joined together in a hexagonal lattice and in diamond, the carbon atom is joined together in a tetrahedral lattice structure. The structural representation of diamond and graphite are different. The basic atom in graphite and diamond is carbon but the arrangement of atoms are different in both the compounds.
Thus, both assertion and reason are correct and reason is the correct explanation of assertion.

So, the correct answer is Option A.

Note: The allotropy is the term only used for elements and not for chemical compounds. For crystalline substances, the term allotropism is known as polymorphism.