Year 5 Science · Reversible and irreversible changes · Summary
Year 5 Science Reversible and irreversible changes: summary and key words
Part of the Year 5 Science reversible and irreversible changes chapter. Chapter overview · whole chapter on one page
Chapter summary
| Skill | Method |
|---|---|
| Reversible changes | Melting and freezing, dissolving (with evaporation) and mixing can be undone, and the material returns. |
| Irreversible changes | Changes that make new materials, such as burning and cooking, are usually not reversible. |
| Acid and bicarbonate of soda | An acid, such as vinegar, reacts with bicarbonate of soda to make new materials and carbon dioxide gas. |
| Evidence | A new colour, a gas, a new smell, or a change that cannot be undone shows a new material has been made. |
| Deciding | Ask whether a new material has been made, and whether the change can be undone. |
Can you…?
- I can say which changes are reversible, such as melting, freezing and dissolving
- I can explain why a change that makes a new material is usually not reversible
- I can describe what happens when an acid reacts with bicarbonate of soda
- I can use evidence to decide whether a change has made a new material
- I can sort changes into reversible and irreversible, and give a reason
Key terms
- reversible change
- a change that can be undone, so that the material returns to how it was
- irreversible change
- a change that cannot easily be undone, usually because a new material is made
- change of state
- a change between solid, liquid and gas, such as melting or freezing
- new material
- a material with different properties, made by a change that cannot easily be undone
- acid
- a substance such as vinegar that reacts with bicarbonate of soda
- bicarbonate of soda
- a white powder that reacts with an acid to make carbon dioxide gas
- carbon dioxide
- a gas that makes bubbles and fizzing when an acid reacts with bicarbonate of soda
- evidence
- something you can see or measure that shows whether a change has happened