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

1 m = 100 cm

1 cm = 10^-2 m

Length of the scale = 20 cm

= 20 × 10^-2 m

Diameter of a carbon atom = 0.15 nm

= 0.15 × 10^-9 m

One carbon atom occupies 0.15 × 10^-9 m.

∴ Number of carbon atoms that can be placed in a straight line

`= (20xx10^(-2)" m")/(0.15xx10^(-9)" m")`

`= 133.33 xx 10^7`

`= 1.33xx10^9`