To find the number of carbon atoms, we <span>multiply </span>the 3.28x10^24 by the ratio, 3/8. The total number of carbon atoms is 1.23 x 10^24 atoms. The total mass of the sample is each number of atoms divided by avogadro's number and multiplied by the molar mass of each. The total mass is 29.96 grams.
The accepted model of the atom was changed.
They have different number of Neutrons and protons, so their masses are different
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