Explanation:
A property that does no change the chemical composition of a substance are known as physical properties.
For example, mass, volume, size etc are all physical properties.
Whereas a property that changes the chemical composition of a substance are known as chemical properties.
For example, reactivity, toxicity etc are all chemical properties.
Therefore, identifying the given statements as follows.
- The various components of a mixture do not combine chemically - physical property.
- Chemical properties can only be observed during a chemical reaction - chemical property.
- The rusting of iron is a chemical reaction - chemical property.
- Melting and boiling points are physical properties - physical property.
