(2009? Han Xiao, a student from Harbin, made an interesting experiment. He added magnesium scraps from the balloon to a conical bottle filled with dilute hydrochloric acid. The whole experiment process. (1) Magnesium reacts with dilute hydrochloric acid to generate hydrogen, which releases heat, thus inflating the balloon. Therefore, when the solid disappears, a large number of bubbles are generated, releasing heat and inflating the balloon.

(2) Magnesium reacts with hydrochloric acid to generate hydrogen, which releases a lot of heat, so that the pressure in the bottle is greater than the external atmospheric pressure, and the balloon will expand. Therefore, the filling: Mg+2HCl═MgCl2+H2↑ increases the gas in the conical bottle, and the exothermic reaction makes the gas expand when heated, and the pressure in the bottle increases, which is greater than the external atmospheric pressure, and the balloon will expand.