Answer is 0.7 g
Reason: Given: mass of Fe = 5.60 gWe know that, half life of Fe-53 = t1/2 (Fe-53) = 8.51 min.
Thus, after 25.53 mins, number of half life passed = 25.53/8.51= 3
Now, Amount left after first half life = 5.60g/2 = 2.80 g
Amount left after second half life = 2.80g/2 = 1.40 g
Amount left after third half-life = 1.40g/2 = 0.7g.
<span>The atoms or molecules attain enough kinetic energy to overcome any intermolecular attractions they have. Since there are no longer any attractive forces between the particles, they are free to drift away into space. The same sort of thing happens in ordinary evaporation, but only at the surface. </span>