Raunak took 5 moles of carbon atoms in a container and Krish also took 5 moles of sodium atoms in another container of the same weight. (a) Whose container is heavier? (b) Whose container has more number of atoms?

(a) The atomic mass of carbon atoms: 12

Thus, the mass of 5 moles of carbon atoms carried by Raunak:


m = Number of moles X Molar mass of given sample


= 5 × 12 = 60g


The atomic mass of sodium atoms:23


Thus, the mass of 5 moles of sodium atoms carried by Krish =


m = 5 ×23 = 115g


Thus, Krish’s container is heavier than Raunak’s container.


(b) The number of atoms = (Given mass)/(Molar mass)


(i) Raunak container (5 moles of carbon atoms):


Number of atoms =


(ii) Krish container (5 moles of sodium atoms):


Number of atoms =


Both containers have the same number of atoms.


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