Question

Which has greater number of atoms-100grams of sodium or 100 grams of iron

Answer 1

Solution :

Atomic mass of Na = 23 u (Given)Then, gram atomic mass of Na = 23 g

Now, 23 g of Na contains = 6.022 x 1023 g number of atoms

Thus, 100 g of Na contains = 6.022 x 1023 / 23 x 100 number of atoms

= 2.6182 x 1024 number of atoms

 Again, atomic mass of Fe = 56 u (Given)

Then, gram atomic mass of Fe = 56 g

Now, 56 g of Fe contains = 6.022 x 1023 g number of atoms

Thus, 100 g of Fe contains = 6.022 x 1023 / 56 x 100 number of atoms

= 1.0753 x 1024 number of atoms