Explanation:
Since, density is the amount of mass present in per unit volume.
Mathematically, Density = [tex]\frac{mass}{volume}[/tex]
As density is directly proportional to mass of a substance. So, more is the density of a substance more will be its mass. And, when more is the mass of a substance then it is likely to sink at the bottom.
Here, it is given that density of oxygen is more than the density of nitrogen. Therefore, balloons filled with oxygen will sink in the air.
On the other hand, balloons filled with nitrogen will rise in the air.
