Conservation of Mass Activity Worksheet (2.03) Instructions: Observe and analyze the interactions between the substances pictured in the slide show. Compare the properties of substances before and after each interaction. You will submit your completed worksheet for grading.

Data Table

On the table below, record your observations before and after the interactions and explain how mass was conserved. Describe the changes in properties that prove a chemical reaction occurred. The first row is an example.

Observations Before Interaction Observations After Interaction How was mass conserved? Proof of a Chemical Reaction

Example: Sugar + Heat

Observations Before Interaction: The sugar is in tiny white particles in a pile. Heat is not seen but is implied by the heat source. The pile of sugar in the pot has a mass of 100 grams.

Observations After Interaction: There is a solid, light brown mass at the bottom of the pot. It has a mass of 100 grams.

How was mass conserved?: The mass of the sugar is the same in melted form as it is in solid crystal form.

Proof of a Chemical Reaction: There was not a chemical reaction. Sugar did not change composition. It only melted. Melting point is a physical property, and this is a physical change.

Substances added:

•Steel Wool + Oxygen (Fire)

•Egg + Heat

•Water + Heat

•Zinc + Hydrogen Chloride

•Sodium Hydroxide + Copper Sulfate