Tijuan mixed a solid and a liquid together in a beaker. He determined that a chemical change occurred. If his conclusion is correct, which substances could he have been observing and why? A) ice mixed into warm oil, because the change of state that occurred when the ice melted cannot be reversed. B) baking soda mixed into vinegar, because the production of bubbles indicates that a new substance formed. C) sugar mixed into hot water, because the disappearance of solid indicates that the chemical identity of the sugar changed. D) sand mixed into water, because when sand was added the mass of the beaker increased.