The melting of ice is considered a physical change because: a it produces a gas.
b a color change occurs.
C. changes the chemical properties of water.
d. produces no new substances, just an appearance change.

When hydrogen peroxide (h2o2) is added to potassium iodide (ki) solution, the hydrogen peroxide decomposes into water (h2o) and oxygen (o2). the chemical equation for the decomposition reaction is: 2h2o2—> 2h2o + o2. what is the role of the potassium iodide in this reaction? a. reactant. b. product. c. precipitate. d. catalyst.