S2.4.3 For the adult
Melting and freezing
Where does my ice go when I leave it in the sun?
What this chapter teaches
Heat turns a solid into a liquid, which is melting. Cooling turns a liquid into a solid, which is freezing. Both can be undone, and the material stays the same. Pure water freezes and ice melts at 0 °C at normal air pressure, and ice floats.
Three questions to ask
There is no one right wording. Listen for the idea.
- Where would butter melt faster, in the sun or in the shade, and why?
- Can a melted thing become solid again? How?
- What do you notice about ice in a glass of water?
After the chapter, the learner can
- Explain melting and freezing as changes caused by heating and cooling
- Compare how fast butter melts in sun and shade
What they copy into their notebook
Heat makes a solid melt into a liquid. Cooling makes a liquid freeze into a solid. Pure water freezes and ice melts at 0 °C. Ice floats. Butter melts faster in the sun than in the shade.