A student puts his signature with graphite pencil. If the mass of carbon in the signature is 10-12 g, calculate the number of carbon atoms in the signature.
No. of atoms in 12 g C = 6.022 × 1023
∴ no. of carbon atoms in 10-12 g
6.022×102312\dfrac{6.022 \times 10^{23}}{12}126.022×1023 x 10-12
= 5.019 × 1010 atoms
