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 length of scale of length 20 cm long.

Explanation

Diameter (d) of carbon atom=0.15 nm=`0.15xx10^(-9)m`
Length of the scale (l)=20cm`=20xx10^(-2)m`
The number of carbon atoms that can be placed along the length of the scale`=(l)/(d)=(20xx10^(-2)m)/(0.15xx10^(-9)m)=1.33xx10^(9)`