it is because a number of factors, including sample surface cleanliness and temperature, can prevent chunks of alkali metals from exploding on contact with water. The team eliminated those variables and others by using a sodium-potassium alloy that remains liquid at room temperature and a droplet delivery system featuring a calibrated syringe.
The volume of iron is obtained from the density formula (density= mass/ volume) given the density and mass. In this case, 3,880 grams of iron and a density of 7.86 g/ml are given. The volume obtained from formula is 493.64 ml or 4.94 dL.