Question 51

The melting of an ice cube in a glass of water is an example of a physical change.

Melting ice is a classic example of a physical change, as it involves a change in the state of matter from solid to liquid without altering the chemical composition of the water.

A) physical change

This option is correct because the melting of ice involves a transition from solid to liquid, which is a physical change. The substance remains H2O throughout the process, demonstrating that no chemical bonds are broken or formed.

B) chemical reaction

This option is incorrect because a chemical reaction involves a transformation that changes the chemical identity of a substance. In the case of melting ice, there is no such transformation; the water remains chemically the same before and after melting.

C) metabolic process

This option is incorrect as metabolic processes refer to the biochemical reactions that occur within living organisms to maintain life. The melting of ice does not involve any biological activity or metabolic changes.

D) decay mechanism

This option is incorrect since decay mechanisms typically refer to the breakdown of organic matter or substances through biological or chemical processes. Melting ice does not involve decay; instead, it is a straightforward physical state change.

Conclusion

The melting of an ice cube is definitively categorized as a physical change, as it involves a change in state while maintaining the same chemical structure. All other options fail to describe the process accurately, either by mischaracterizing the nature of the change or by relating it to unrelated concepts.