Lesson · Grade 2 · Science
Cooking and Burning: Changes You Cannot Undo
- Grade 2
- Science
- 1 min 6 s
- British Columbia
- BC2-SC-07
Heat turns bread into toast, toast into burnt toast, and batter into cake, and a crossed-out arrow back shows that none of them can change back. Melted chocolate goes hard again when it cools, which shows that melting is a change we can undo, unlike toasting, baking and burning.
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In one sentence
The question this lesson answers
In the kitchen, heat can change our food.
Heat turns soft bread into crunchy toast.
Transcript
What the lesson says
In the kitchen, heat can change our food.
Heat turns soft bread into crunchy toast.
Can we change toast back into bread?
No. Toast can never be bread again.
More heat makes the toast burnt and black.
Burnt toast cannot change back either.
Heat turns runny batter into soft cake.
Can cake change back into batter? No.
Heat turns hard chocolate into melted chocolate.
Let it cool, and it goes hard again.
Melting is a change we can undo.
Toasting, baking and burning are changes we cannot undo.
Curriculum
Where this fits
The outcomes and strands follow the British Columbia curriculum.
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