Mrs. Clark decides to do a demonstration for her class with a piece of notebook paper. Using a balance, Mrs. Clark discovers that the mass of the paper is 20 g. She then takes the piece of paper and cuts it into several small pieces. The cumulative mass of the small pieces is 20 g. What has Mrs. Clark demonstrated for her class?

Question

Mrs. Clark decides to do a demonstration for her class with a piece of notebook paper. Using a balance, Mrs. Clark discovers that the mass of the paper is 20 g. She then takes the piece of paper and cuts it into several small pieces. The cumulative mass of the small pieces is 20 g. What has Mrs. Clark demonstrated for her class?
 A. 
a physical change involving change of mass
 B. 
a chemical change involving change of shape and size of matter
 C. 
a physical change involving change of shape and size of matter
 D. 
a chemical change involving change of mass

GPT-4o mini · Answer

Mrs. Clark has demonstrated **C. a physical change involving change of shape and size of matter**. The cutting of the paper is a physical change because it alters the shape and size of the paper without changing its chemical composition or mass, which remains constant at 20 g before and after the cutting.