Question bank: Everyday Materials Transformations

Joãozinho is helping his mother in the kitchen and left a glass of water on the counter. He came back later and saw that the water was warm. Thinking about what happened, Joãozinho remembered that the water in the glass heated up because it was near the stove, which was on. Now, think about the things you have at home, like plastic, glass, and metal. If you put these materials in the freezer, what do you think will happen to each of them and why? Explain the changes that can occur in each material when exposed to different temperatures, using what you have already learned about how heat and cold transform things.

Imagine you have a piece of chocolate and an ice cube on a hot summer day. Describe what happens to each of them after some time in the sun and explain why these transformations occur.

When we play with modeling clay, we can create different shapes and figures. But what happens to the clay if we leave it in the sun for a long time? Or if we put it in the freezer? Also, think about when you leave a fruit out of the fridge for too long. The fruit changes, right? Now, write about how some everyday materials, such as modeling clay and fruits, can change when exposed to different conditions, such as heat, cold, light, and humidity.

Think about the objects we use every day, like the water we boil to make tea, the ice cream that melts in the heat, or the rubber that hardens when not used for a long time. These are some transformations of materials that happen in our daily lives. Now, I want you to look around and think about a common material, like the plastic of a shopping bag we use. Imagine what could happen to this plastic if it were exposed to the sun for several days. Write about how you think the plastic bag would change and why this would happen.

In school, the 4th-grade students were conducting an experiment to understand how different conditions can change the characteristics of a substance. They observed what happened to a piece of butter when placed in the freezer and then in the sun, noting that the butter hardened in the freezer and melted in the sun. Considering this experiment, explain how the state transformations of butter, from solid to liquid and vice versa, are related to the temperature conditions observed in the experiment. Describe what happens at a molecular level when heat is added to the solid and removed from the liquid. (Remember that butter is mainly composed of fats, water, and proteins, and each component has its own melting and boiling temperature.)