Hydrogen peroxide breaks down to form water and oxygen gas. Which observation is evidence that a chemical reaction has occurred?
A. Phase changes are observed.
B. The color of the solution remains clear.
C. The temperature of the solution increases.
D. The mass of the solution remains the same.
1 answer
C. The temperature of the solution increases is evidence that a chemical reaction has occurred. When hydrogen peroxide breaks down to form water and oxygen gas, energy is released in the form of heat, causing the temperature of the solution to increase. This is an indicator that a chemical reaction has occurred. Option A, B, and D do not show any signs of a chemical reaction.
1 answer