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Question
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.
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Solution
12g of carbon contains = 6.023 x 1023 number of carbon atoms.
10-12g of carbon will contain = `(6.023 xx 10^23 xx 10^(-12))/12`
= 0.5019 x 1011
= 5.019 x 1010
So,the number of carbon atoms in the signature is 5.019 x 1010
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