A signature, written in carbon pencil weighs 1 mg. what is the number of carbon atoms present in the signature?

Options

A. `5.02xx10^(23)`
B. `5.02xx10^(20)`
C. `6.02xx10^(20)`
D. `0.502xx10^(20)`

Answer

D

Explanation

1mg=`1xx10^(-3)g`
`because` 12g carbon contains=`6.023xx10^(23)` carbon
atoms
`therefore1xx10^(-3)` g carbon contains
`=(6.023xx10^(23))/(12)xx1xx10^(-3)`
`=0.502xx10^(20)` carbon atoms.