question_answer 56)

The diameter of zinc atom is 2.6 A. Calculate : (a) radius of zinc atom in pm and (b) number of atoms present in a length of 1.6 cm if the zinc atoms are arranged side by side length wise.

Answer:

(a) \[r=\frac{1}{2}\times d=\frac{1}{2}\times 26\overset{{}^\circ }{\mathop{\text{A}}}\,=1.3\overset{{}^\circ }{\mathop{\text{A}}}\,\] \[=1.3\times {{10}^{-10}}m=130\times {{10}^{-12}}m=130pm\] (b) Let x atoms are present side by side. \[x\]x diameter = 1.6 cm \[x\times 2.6\times {{10}^{-8}}cm=1.6\] \[x=6.154\times {{10}^{7}}atoms\]