Question

mole is the amount of substance of system which contains many elementary and entities as three atoms in ........... of carbon-12.
(A) 0.012 gram
(B) 12 kilograms
(C) 0.12 kilogram
(D) 0.012 kilogram​

Answer 1

Explanation:

The mole was defined by International Bureau of Weights and Measures as "the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon-12." Thus, by that definition, one mole of pure 12C had a mass of exactly 12 g.