In a science demonstration, a teacher mixed zinc (Zn) with hydrogen chloride (HCl) in a flask and quickly attached a balloon over the mouth of the flask. Bubbles formed in the solution and the balloon inflated.
What most likely occurred during this demonstration?
:The Zn and HCl both retained their identity.
:Either Zn or HCl, but not both, retained its identity.
:Evaporation of one of the substances occurred.
:One or more new substances formed.