Part 3 of 4: States of Matter

Which of the following is a characteristic of a physical change of matter?

• The change creates a new substance.

• The change requires a chemical reaction.

• The change requires increased temperature.

• The change creates a different form of the existing substance.

In class, Johari and Micah observed Ms. Miller's experiment with water. She started with an ice cube, heated it up to boiling, and then she removed the heat source. Which observation could be used in an argument to support Ms. Miller's claim that physical changes to the state of water had taken place?

• The ice changed from a solid to a gas as the heat energy decreased.

• The ice changed from a solid to a liquid as the heat energy decreased.

• The ice melted, changing from a solid to a liquid as the heat energy increased.

• The ice boiled and changed from a gas to a liquid as the heat energy increased.

Tyrone claims that physical changes in the state of water are caused by changes in temperature. Based on their observations, which argument BEST describes the validity of Tyrone’s claim?

• Tyrone is incorrect because the temperature in the room did not change.

• Tyrone is incorrect because he did not use a burner to add heat to the ice cube.

• Tyrone is correct because the warmer temperature in the room caused the ice to melt.

• Tyrone is correct because all physical changes are caused by changes in temperature.

Mr. Elton was teaching his class about physical and chemical changes. As part of his instruction, he brought an electric toaster to class and demonstrated what happened when a piece of bread was placed inside and heated. After the demonstration, he asked his students to visit the class blog to post their observations. Which student provided the BEST observation to support his or her thinking about the change that occurred when Mr. Elton made toast?

• Penny

• Jonas

• Liam

• Neil

Which student’s investigation will create a chemical change?

• Carrie

• Ernest

• Jenny

• Michael