Which has more atoms, 100 grams of sodium or 100 grams of iron (given atomic mass of Na = 23 u, Fe = 56 u)?
23g of Na = 6.022 x 1023 atoms (1 mole)
Therefore, 100g of Na =( 100x 6.022x 1023)/23
= (602.2)/23 x1023
= 26.182 x 1023
= 2.6182 x 1024 atoms
56g of Fe = 6.022 x 1023 atom
Therefore 100g of Fe =( 100 x 6.022 x 1023)/56
= (602.2 x1023)/56
=10.753 x 1023
=1.075 x 1024
100g of Na - 2.6182 x 1024 atoms
100g of Fe - 1.075 x 1024
Therefore, 100g of Na contain more atoms.
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