Let’s go through each statement one by one and decide if it’s true or false based on what we know about physical and chemical changes.
Physical change: The substance looks different, but it’s still the same stuff. You can usually reverse it (like melting ice → freezing water again). No new substance is made.
Chemical change: A new substance is formed. It’s often hard to reverse (like burning wood → ash and smoke). Signs include color change, gas produced, heat/light released, etc.
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1.
Evaporation is a physical change.
→ Water turns from liquid to gas, but it’s still H₂O. Can be reversed by condensation.
✔ TRUE
2.
Ice cream melting is a chemical change.
→ Melting just changes state — solid to liquid. Still ice cream! Can freeze it back.
✘ FALSE
3.
Wood burning is a physical change.
→ Burning makes ash, smoke, CO₂ — totally new substances. Can’t un-burn wood.
✘ FALSE
4.
Water mixing with oil is a physical change.
→ They don’t react chemically — just sit apart. You can separate them physically.
✔ TRUE
5.
Air inflating a tire is a chemical change.
→ Air is just being pushed in — no reaction happening. Same air molecules.
✘ FALSE
6.
Marshmallows roasting on a fire is a chemical change.
→ Roasting causes browning, caramelization, maybe even charring — new substances form. Smell/taste change = chemical change.
✔ TRUE
7.
Marshmallows cut in half is a chemical change.
→ Just changing shape/size. Still marshmallow inside.
✘ FALSE
8.
Chemical changes can be easily reversed.
→ Usually NOT easy. Think: you can’t “un-bake” a cake or “un-rust” iron.
✘ FALSE
9.
Physical changes can be easily reversed.
→ Often yes — melt/freezing, dissolve/evaporate, stretch/compress. Not always *perfectly* reversible, but generally easier than chemical.
✔ TRUE (for most school-level examples)
10.
Fermenting cheese and grating cheese are both physical changes.
→ Grating = physical (just smaller pieces). Fermenting = chemical (bacteria make new flavors/textures — lactic acid, etc.). So not BOTH physical.
✘ FALSE
11.
Freezing water into ice cubes is a physical change.
→ State change only. Still H₂O. Can melt back.
✔ TRUE
12.
Iron rusting is a chemical change.
→ Rust is iron oxide — new substance formed when iron reacts with oxygen and water. Hard to reverse.
✔ TRUE
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Final Answer:
1. True
2. False
3. False
4. True
5. False
6. True
7. False
8. False
9. True
10. False
11. True
12. True
Parent Tip: Review the logic above to help your child master the concept of physical chemical changes worksheet.