5th grade · Science · Unit 4 of 9
Physical or Chemical?
Changes that make new things
What your child practices
Telling a physical change from a chemical change, spotting the signs of a new substance, and how making and throwing away everyday products affects the environment.
Maine Learning Results learning standard: 5-PS1-4 · mixing substances that react and make new substances
How we explain it
Children can open this short lesson before they practice.
- A physical change alters size, shape or state, but no new substance is made.
- Melting, crushing, cutting and dissolving are physical changes.
- A chemical change makes a new substance, like rusting or burning.
- Signs of a chemical change: gas bubbles, a new smell, color change or light and heat.
Example: Wood burns and turns to ash and smoke. Physical or chemical change? Ash and smoke are new substances. New substances mean a chemical change. Answer: chemical change
Physical or Chemical? in Maine
In the Maine Learning Results, this is unit 4 of 9 in 5th grade Science, after Changes of State and before Measuring Matter.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Source: Maine Department of Education
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Which is a chemical change?
- Cutting bread
- Baking bread dough
- Freezing bread
Baking bread dough
Hint: Baking creates new substances that were not in the dough.
Question 2
Cutting paper into small pieces is a…
- chemical change
- physical change
- change that makes a new substance
physical change
Hint: The pieces are still paper. No new substance forms.
Question 3
Which of these is NOT a good sign of a chemical change?
- A new color appears
- Something gets bigger
- A new smell appears
- Heat or light is given off
Something gets bigger
Hint: A change in size alone can happen in a physical change.
Question 4
Sugar is stirred into tea and seems to disappear. This is a…
- change of state to a gas
- chemical change
- physical change
physical change
Hint: The sugar is still there, and you could taste it. No new substance formed.
Question 5
Ice is melted, then the water is boiled. Which statement is correct?
- Both are physical changes
- Both are chemical changes
- Melting is chemical and boiling is physical
Both are physical changes
Hint: Ice, water and steam are all the same substance, so no new substance formed.
Question 6
Wax melts near a candle flame, while the wick burns. Why is only the burning a chemical change?
- Melting makes new gases
- Burning does not change the wick
- Burning makes new substances; melting does not
Burning makes new substances; melting does not
Hint: Look for whether a new substance forms.