Question

If the diameter of a carbon atom is 0.15 nm, calculate the number of carbon atoms which can be placed side by side in a straight line across the length of scale of length 20 cm long.

Answer 1

Diameter of carbon atom `= 0.15 nm = 0.15 xx 10^(-9) m = 1.5 xx 10^(-10)m`
Length along which atoms are to be placed `= 20 cm = 20 xx 10^(-2) m = 2 xx 10^(-1)m`
`:.` No. of C-atoms which can be placed along the line `= (2 xx 10^(-1))/(1.5 xx 10^(-10)) = 1.33 xx 10^(9)`