Dalton and Macie determines that a
Chemical change
Physical change
Must have taken place
for the following observations:
1. A piece of wood burning and turning into ash - Chemical change
2. A glass of ice melting into liquid water - Physical change
3. Mixing vinegar and baking soda to produce bubbles and a fizzing sound - Chemical change
4. Chopping a carrot into smaller pieces - Physical change
5. Rust forming on a metal surface - Chemical change
6. Dissolving sugar in water - Physical change
7. Cooking an egg and changing its texture and color - Chemical change
8. Freezing water into ice cubes - Physical change
9. Mixing oil and water and seeing them separate into distinct layers - Physical change
10. A piece of fruit decomposing and releasing a foul odor - Chemical change
To determine whether a chemical change or a physical change has taken place, Dalton and Macie can look for specific signs or characteristics of each type of change.
Physical Change:
- A physical change does not alter the chemical composition or identity of a substance.
- The physical state or appearance of the substance may change, but its chemical properties remain the same.
- Some examples of physical changes include changes in size, shape, phase (solid, liquid, gas), melting, freezing, boiling, dissolving, or condensation.
Chemical Change:
- A chemical change occurs when the chemical composition or identity of a substance is altered.
- One or more new substances are formed with different chemical properties.
- Some examples of chemical changes include burning, rusting, rotting, cooking, digestion, decomposition, or fermentation.
If Dalton and Macie can identify any of the following signs, it indicates that a chemical change has likely taken place:
- Production of gas (bubbling or fizzing)
- Formation of a solid precipitate
- Release or absorption of energy in the form of heat, light, or sound
- Color change
- Production of an odor or smell
If they observe any of these signs, then it is likely that a chemical change has occurred. However, if none of these signs are present and only a physical change is observed, then a physical change must have taken place.