Question

Match the primitive unit cells given in Column I with their axial angles and axial distances given in Column II and select the correct answer from the codes given.

• A. (i)-r, (ii)-s, (iii)-p, (iv)-q
• B. (i)-r, (ii)-s, (iii)-q, (iv)-p
• C. (i)-s, (ii)-r, (iii)-p, (iv)-q
• D. (i)-p, (ii)-q, (iii)-r, (iv)-s

Answer 1

The correct option is C (i)-s, (ii)-r, (iii)-p, (iv)-q

(i) In Orthorhombic, all the axial angles are equal to ${90}^{\circ }$ while all the edge lengths are uneual.
$\alpha =\beta =\gamma ={90}^{\circ }$, $a\ne b\ne c$
(i)$\to s$

(ii) In Monoclinic, all the edge length are different and two axial angle is equal to ${90}^{\circ }$ $\alpha =\gamma ={90}^{\circ }\ne \beta ,a\ne b\ne c$
(ii) $\to r$

(iii) In Hexagonal, edge length of two sides are equal and two axial angles are equal to ${90}^{\circ }$
$\alpha =\beta ={90}^{\circ },\gamma ={120}^{\circ },a=b\ne c$
(iii) $\to p$

(iv) In cubic, all the edge length are equal and axial angles are equal to ${90}^{\circ }\alpha =\beta =\gamma ={90}^{\circ },a=b=c$