To determine which changes shown in the table are physical changes, we need to identify which changes do not produce new substances. Physical changes typically involve alterations in physical properties (like state, shape, or appearance) without changing the chemical composition of the substance.
Looking at the table:
- Change 1: Reacts with another substance? Yes (Chemical change); Temperature change? Yes; Gas, sound, or light produced? Yes; New substance formed? Yes.
- Change 2: Reacts with another substance? No (Physical change); Temperature change? Yes; Gas, sound, or light produced? Yes; New substance formed? No.
- Change 3: Reacts with another substance? Yes (Chemical change); Temperature change? Yes; Gas, sound, or light produced? Yes; New substance formed? Yes.
- Change 4: Reacts with another substance? No (Physical change); Temperature change? No; Gas, sound, or light produced? No; New substance formed? No.
Based on this analysis:
- Change 2 qualifies as a physical change, as it does not react with another substance and does not form a new substance.
- Change 4 also qualifies as a physical change since it does not react with another substance and does not form a new substance.
Therefore, the changes that are physical changes are Changes 2 and 4.
So the correct response is: 2 and 4.