Question

read the passage and answer the following question(s). passage 5143 directions: the diagram shows a test tube of copper (ii) sulfate solution before and after the addition of iron shavings during an experiment. use the diagram to answer any questions that follow. the experiment shows a a. physical reaction, because it involved a compound. b. physical reaction, because the solution changed color. c. chemical reaction, because the solution changed color. d. chemical reaction, because it involved a mixture.

Explanation:

Step1: Recall reaction - type criteria

Physical reactions do not change the chemical composition of substances, while chemical reactions result in the formation of new substances. Color - change is often an indication of a chemical reaction.

Step2: Analyze the experiment

When iron shavings are added to copper (II) sulfate solution, a chemical reaction occurs. The iron displaces copper from copper (II) sulfate according to the reaction: $Fe + CuSO_{4}
ightarrow FeSO_{4}+Cu$. The change in color from blue to greenish - yellow and brownish - red indicates the formation of new substances (iron (II) sulfate and copper). This is a chemical reaction, not a physical reaction.

Answer:

C. chemical reaction, because the solution changed color.