Problem Description:
The task involves identifying whether each image represents a
physical change or a
chemical change. The images provided are:
1. A flame burning.
2. A hand holding a lit matchstick.
3. A snowman melting.
Solution Explanation:
####
Step 1: Understand the Definitions
-
Physical Change: A change in which the physical properties of a substance (such as shape, size, state, etc.) are altered, but the chemical composition remains the same. No new substances are formed.
-
Chemical Change: A change in which the chemical composition of a substance is altered, resulting in the formation of new substances with different properties. This often involves the breaking and forming of chemical bonds.
####
Step 2: Analyze Each Image
1.
Flame Burning (Image 1):
- When a flame burns, it involves combustion, where oxygen reacts with fuel (e.g., wood, gas) to produce heat, light, carbon dioxide, and water. New substances (carbon dioxide and water) are formed.
-
Conclusion: This is a
chemical change because new substances are created.
2.
Hand Holding a Lit Matchstick (Image 2):
- Lighting a matchstick involves combustion, similar to the flame burning. The matchstick reacts with oxygen in the air, producing heat, light, and new substances like carbon dioxide and water.
-
Conclusion: This is a
chemical change because new substances are formed during the reaction.
3.
Snowman Melting (Image 3):
- Melting is a process where ice (solid water) changes into liquid water. The chemical composition of water (H₂O) remains the same; only its physical state changes from solid to liquid.
-
Conclusion: This is a
physical change because no new substances are formed, only a change in state occurs.
####
Step 3: Assign Labels
Based on the analysis:
-
Flame Burning: Chemical change
-
Hand Holding a Lit Matchstick: Chemical change
-
Snowman Melting: Physical change
Final Answer:
\[
\boxed{
\begin{array}{ll}
\text{Flame Burning} & \text{Chemical change} \\
\text{Hand Holding a Lit Matchstick} & \text{Chemical change} \\
\text{Snowman Melting} & \text{Physical change} \\
\end{array}
}
\]
Parent Tip: Review the logic above to help your child master the concept of physical chemical changes worksheet.
