This science worksheet helps students visualize the difference between physical and chemical changes through a fun coloring exercise.

It looks like you've uploaded a worksheet titled "Let's color" with a science activity focused on identifying whether different scenarios represent physical or chemical changes. The goal is to:

1. Choose a color code (likely C for chemical and P for physical).
2. Color each image based on whether the process shown is a physical change or a chemical change.

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🔍 Understanding Physical vs. Chemical Changes

- Physical Change: A change in form or state, but the substance remains the same chemically.
- Examples: melting ice, breaking a pencil, cutting paper.
- No new substances are formed.

- Chemical Change: A change where new substances are formed due to a chemical reaction.
- Examples: burning wood, rusting metal, cooking food.
- Often involves color change, gas production, or heat release.

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✔ Let's Analyze Each Image

Here’s the list of images and their classifications:

#### Row 1:
1. Fireworks → 💥 Chemical (combustion produces new substances) → C
2. Flat tire → 🚴‍♂️ Physical (air escaped, but no chemical change) → P
3. Digesting a tomato → 🍅 Chemical (enzymes break down food into new molecules) → C
4. Unscrewing a cap → 🔧 Physical (just removing a cap, no chemical change) → P

#### Row 2:
5. Shopping cart → 🛒 Physical (no change in material; just moving it) → P
6. Breaking a cup → 🥤 Physical (shattering glass, still glass) → P
7. Rusty bicycle → 🚲 Chemical (rust = iron + oxygen → iron oxide) → C
8. Car crash → 🚗 Physical (deformation, but materials unchanged) → P

#### Row 3:
9. Chewing food → 🍽️ Physical (mechanical breakdown, not digestion yet) → P
10. Making ice cream → 🍦 Physical (freezing mixture, no chemical reaction) → P
11. Digestion → 🍎 Chemical (breaking down food into nutrients via enzymes) → C
12. Cleaning up a spill → 🧼 Physical (just wiping, no chemical change) → P

#### Row 4:
13. Breaking a pencil → ✏️ Physical (wood breaks, no new substance) → P
14. Blowing up a balloon → 🎈 Physical (air expands, but air stays the same) → P
15. Heating sugar in water → 🔬 Physical (dissolving, not reacting) → P
16. Slicing bread → 🍞 Physical (cutting, not changing composition) → P

#### Row 5:
17. Cooking sausages → 🌭 Chemical (browning, proteins denature, Maillard reaction) → C
18. Chopping wood → 🪓 Physical (cutting, no chemical change) → P
19. Ice melts → ❄️ Physical (solid to liquid, H₂O stays H₂O) → P
20. Blow drying wet hair → 💁‍♀️ Physical (evaporation of water from hair) → P

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🎨 Final Answer Key (Color Code):

| Image | Process | Type | Code |
|------|--------|------|------|
| 1 | Fireworks | Chemical | C |
| 2 | Flat tire | Physical | P |
| 3 | Digesting a tomato | Chemical | C |
| 4 | Unscrewing a cap | Physical | P |
| 5 | Shopping cart | Physical | P |
| 6 | Breaking a cup | Physical | P |
| 7 | Rusty bicycle | Chemical | C |
| 8 | Car crash | Physical | P |
| 9 | Chewing food | Physical | P |
| 10 | Making ice cream | Physical | P |
| 11 | Digestion | Chemical | C |
| 12 | Cleaning up a spill | Physical | P |
| 13 | Breaking a pencil | Physical | P |
| 14 | Blowing up a balloon | Physical | P |
| 15 | Heating sugar in water | Physical | P |
| 16 | Slicing bread | Physical | P |
| 17 | Cooking sausages | Chemical | C |
| 18 | Chopping wood | Physical | P |
| 19 | Ice melts | Physical | P |
| 20 | Blow drying wet hair | Physical | P |

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✔ Instructions for Coloring:

- Use one color (e.g., red) for Chemical (C).
- Use another color (e.g., blue) for Physical (P).
- Color each box accordingly.

> ⚠️ Note: "Heating sugar in water" is physical if it's just dissolving. But if it's caramelizing (turning brown), that would be chemical. Based on the image (likely just dissolving), we assume physical.

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🧠 Summary

- Most changes involving breaking, cutting, freezing, melting, or mixing without reaction are physical.
- Changes involving burning, rusting, digesting, cooking, or decomposing are chemical.

Let me know if you'd like a printable version or a colored PDF!