Nio conducts a science experiment. He puts yeast into a bottle with water and sugar, and then caps the bottle with a balloon. He returns two hours later and notices there are bubbles on the surface of the mixture in the bottle and that the balloon has inflated, but there are no other apparent changes.
A
a non-chemical change, because there are no indicators of chemical changes taking placeB
a chemical change, because the mixture changed colorC
a chemical change, because a gas was producedD
a non-chemical change, because the changes that occurred are reversible