Question

What do these two changes have in common?

1) They both involve mixing substances.
2) They both result in a change in appearance.
3) They both involve the movement of particles.
4) They both occur naturally.

Answer 1

Physical changes alter the appearance of a substance without changing its molecular structure, while chemical changes involve the transformation of one substance into another. Both physical and chemical changes can involve mixing substances and result in a change in appearance. Additionally, chemical changes also involve the movement of particles.

Step-by-step explanation:

In a physical change, the appearance of a substance may change, but its molecular structure remains the same. Examples of physical changes include melting ice, evaporating water, and weathering mountains. On the other hand, a chemical change involves the transformation of one substance into another, resulting in the formation of new substances with different properties. Chemical changes often involve the mixing of substances and the movement of particles. For example, when gasoline burns, it reacts with oxygen in the atmosphere to form carbon dioxide gas and water vapor, resulting in a change in appearance and the movement of particles.