19 Physical vs. Chemical Changes
👩🏫 Teacher’s Guide
Objective
Students will distinguish changes that alter form from those that create new substances.
Vocabulary
physical change, chemical change, evidence, irreversible, reaction
Teaching Notes
- Start with a quick demo or model to visualize the concept.
- Pre-teach key vocabulary with gestures or sketches.
- Prompt students to predict, observe, and explain in full sentences.
- Check for understanding using either/or and short-answer prompts.
🧒 Student Worksheet
Concept and Helping Material
No videos found.
Definition. Physical changes keep the same substance; chemical changes create new substances with different properties.
Helping ideas and samples:
- Try a quick sort, draw-and-label, or compare-and-contrast.
- Name one place you see this idea at home or at school.
- Safety: follow teacher directions and handle materials carefully.
Vocabulary and Definition
- — a change in size, shape, or state without new substances
- — a change that makes new substances
- — signs that a change occurred
- — cannot be easily changed back
- — process where substances change into new ones
Words to Learn
, , , ,
Sentences to Fill In
1. Melting ice is a __ change.
2. Rusting iron is a __ change.
3. Bubbling gas can be __ of a chemical change.
4. Burning paper is usually __ to reverse.
5. A chemical __ makes new substances.
Hands-On Experiment or Activities
What You Need: simple classroom items.
What You Do: Fizz test: mix vinegar and baking soda; observe gas, temperature change, and new substances forming.
Think and Talk: What changed? What stayed the same?
Reflection
- Why is dissolving sugar in water a physical change?
- Which evidence helped you decide the fizz test was chemical?