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 lengthwise.

Explanation

(i) Diameter of zinc atom = `2.6 Å = 2.6 xx 10^(-10) m`
Radius = `(2.6 xx 10^(-10))/(2)`
`= 1.3 xx 10^(-10) m = 130 xx 10^(-12) m`
`= 130 p m`
(ii) No. of Zn atoms present on a 1.6 cm length = `(1.6)/(2.6 xx 10^(-10) xx 10^2) = 6.154 xx 10^7`.