Step-by-step explanation:
A change in physical property, such as changing the shape, size, or state of matter, does not change the identity of the substance because these changes only alter the physical characteristics of the substance, not its chemical composition.
The identity of a substance is determined by its chemical composition and the types of atoms or molecules it contains. This composition remains the same regardless of changes in physical properties. For example, if you melt a solid ice cube, it turns into liquid water, but it is still composed of the same H2O molecules. Similarly, if you boil the liquid water, it turns into a gas, but the chemical composition remains unchanged.
In contrast, a change in chemical properties involves a rearrangement or transformation of the atoms or molecules in a substance, resulting in the formation of new substances with different chemical compositions. These changes can alter the identity of the substance. For example, when iron reacts with oxygen in the presence of moisture, it forms iron oxide, also known as rust. In this case, the chemical composition of iron has changed, and it is no longer the same substance.
So, while changes in physical properties affect the appearance or behavior of a substance, they do not alter the underlying chemical identity of the substance.