Question

Assertion (A) : Graphite is an example of tetragonal crystal system.
Reason (R) : For a tetragonal system, $a=b\ne c$ and $\alpha =\beta ={90}^o,\gamma ={120}^0$.

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correc but (R) is incorrect
• D. (A) is incorrect but (R) is correct
• E. Both (A) and (R) are incorrect

Answer 1

Answer: (E)

Both (A) and (R) are incorrect

Correct (A): Graphite is an example of hexagonal crystal system in which each $C-$ atom is $s{p}^2$ hybridized and is linked to three other $C-$ atom in a hexagonal planar structure. Correct $\left(R\right)$ : For tetragonal system, $a=b\ne c$ and $\alpha =\beta =\gamma ={90}^{\circ }.$ For hexagonal systems, $a=b\ne c$ and $\alpha =\beta ={90}^{\circ },\gamma ={120}^{\circ }$