Question

Q22- Which of the given statements is not a physical change? A) Boiling of water to give water vapour B) Melting of ice to give water C) Dissolution of salt in water D) Combustion of Liquefied Petroleum Gas (LPG)​

Answer 1

Explanation:

- As from the discussion we can consider that a physical change involves only change in physical state whereas a chemical change results in the formation of new substances. Boiling of water, melting of ice and dissolution of salt are physical changes as no new products are formed. So, the correct answer is “Option D”.

Answer 2

Of the given statements D) Combustion of Liquefied Petroleum Gas (LPG) is not a physical change

• Since after boiling there's no change in the chemical structure of water hence, it's a physical change. So, option A) Boiling of water to give water vapour is correct.
• Similarly, in melting of ice to give water is also a physical change because in this case only change in physical state has taken place not the chemical structure of water. Hence B is correct answer.
• Dissolution of salt in water is a physical change because it is reversible in nature and salt can be recovered by evaporation. Hence, C) is correct answer.
• Combustion of Liquefied Petroleum Gas (LPG) is a chemical change because it's not reversible and it produces carbon dioxide and water as product. Hence, option D is incorrect.