Question

Number of atoms in 558.5 gram Fe (at. wt. of Fe = 55.85 gmol⁻¹) is(a) twice that in 60 g carbon(b) 6.023 x 10²²(c) half that in 8 g He(d) 558.5 x 6.023 x 10²³

Answer 1

One mole is the amount of a substance that contains as many particles or entities as there are atoms in exactly 12 g (or 0.012 kg) of the 12C isotope.

- wherein

one mole = 6.0221367 X 1023

Number of moles of Fe atom =\frac{558.5}{55.85}=10\ Mole

Total number of atom =10\times 6.022\times 10^{23}=6.022 \times10^{24}

6.022 \times10^{24} no. of atoms found in 120 gm carbon.

Ans. Option (1)

twice that in 60 g carbon