Answer:
Ice is a solid form of liquid. Water simply expands when it freezes.
The same amount of water for each shape of ice because the melting rate of ice depends on the surface area of each shape. So the same amount of water or volume with a large surface area will remain frozen for longer time.
30% should be the percentage of oxygen if the total mass of fe2o3 is 160.
The one with higher mass has a higher density because it fits more mass into the same amount of space (volume).
The liquid will stop converting into vapor. This process is to balanced the amount of substance of both phases inside the flask.
