Lauren, a chemistry student, makes the following claim: My results showed that even more energy was lost during combustion during the food burning compared to burning pentanol. I think this is because the large flames and fast burning caused more energy to be lost to the surroundings. Also, I could see smoke during the combustion, showing that not all the fuel was burned. Does this match your results?

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

it's all four options.