Which type of change involves no new substances being formed, only rearrangement of atoms and molecules?

Which type of change involves no new substances being formed, only rearrangement of atoms and molecules?

• A. Physical Changes
• B. Chemical Changes
• C. Phase Changes
• D. Nuclear Changes

Answer: (A)

The concept here is that if no new substance is formed, you’re looking at a physical change. In a physical change, the material’s identity stays the same—its molecules aren’t bonded together to form something new, they might just rearrange or shift state. Ice melting into water is a prime example: the same H2O molecules, just in a liquid form, so no new substance appears. Phase changes—solid, liquid, gas—are all physical changes because they involve changes in state, not in chemical composition. By contrast, chemical changes create new substances by breaking and forming bonds, and nuclear changes involve changes in the nucleus itself. So the situation described fits physical change.

The concept here is that if no new substance is formed, you’re looking at a physical change. In a physical change, the material’s identity stays the same—its molecules aren’t bonded together to form something new, they might just rearrange or shift state. Ice melting into water is a prime example: the same H2O molecules, just in a liquid form, so no new substance appears. Phase changes—solid, liquid, gas—are all physical changes because they involve changes in state, not in chemical composition. By contrast, chemical changes create new substances by breaking and forming bonds, and nuclear changes involve changes in the nucleus itself. So the situation described fits physical change.