Question

How will you justify that ice, water, and steam are not different substances, but different states of the same substance?

Answer 1

• Ice, water, and steam consist of the same constituent elements (i.e., hydrogen and oxygen), same molecules, and same chemical properties
• Melting changes ice into the water there is a change in its form i.e, from solid to a liquid state.
• On freezing, water changes its state from liquid to solid, and as a result ice is formed.
• On boiling, this water state of matter changes from liquid to gas, i.e, steam. And when we condense this steam, it forms water.
• Therefore, we can say that there is only a change in the state of matter by changing the temperature.
• Ice - water - steam are the three different states of a substance and not different substances.
• Ice on heating$\to$ (melts to) water on further heating $\to$ (by evaporation) gas
  Gas by condensation $\to$water on freezing $\to$ ice.