Which of the following observations is/are examples of physical change?
1) The density of water decreases when it solidifies.
2) Aluminum melts when heated above 660 $^{\circ}$ C.
3) Hydrogen peroxide (H₂O₂) decomposes to water and oxygen.

Question

Which of the following observations is/are examples of physical change?
1) The density of water decreases when it solidifies.
2) Aluminum melts when heated above 660

^{\circ}

C.
3) Hydrogen peroxide (H₂O₂) decomposes to water and oxygen.

Quizplus · Accepted Answer

Physical changes involve changes in physical properties without altering the chemical composition. Both the decrease in density of water when it solidifies and the melting of aluminum are physical changes. The decomposition of hydrogen peroxide is a chemical change.

Which of the Following Observations Is/are Examples of Physical Change ∘^{\circ}∘

Which of the Following Observations Is/are Examples of Physical Change $^{\circ}$