Question

Based on the student's observations in the test tube where two clear liquids were mixed, including the test tube feeling warmer, bubbles forming on the sides, and a blue solid forming on the bottom, construct an evidence-based argument to support a claim about what type of change occurred in the test tube.

Please provide your argument with supporting evidence.

Answer 1

A chemical change occurred in the test tube, evidenced by a temperature increase, bubble formation, and the creation of a new blue solid, or precipitate.

Step-by-step explanation:

Based on the observations in the test tube, where two clear liquids were mixed and resulted in the test tube feeling warmer, bubbles forming on the sides, and a blue solid forming on the bottom, we can argue that a chemical change occurred in the test tube. The evidence supporting this includes the temperature change, which is indicative of an exothermic reaction where heat is released to the surroundings. Additionally, the formation of bubbles signifies the production of a gas. This is not due to boiling, suggesting a new substance is being formed. Lastly, the unexpected color change resulting in a blue solid, or precipitate, further corroborates that a chemical reaction took place, as a new substance with properties different from the reactants was created.