Teaching demonstration instrument

The utility model relates to teaching instruments, in particular to a teaching demonstration instrument. The teaching demonstration instrument is characterized in that a fulcrum bar is arranged on a workbench, a hang arm is arranged on the fulcrum bar, a demonstration bottle is arranged on the hang arm, an opening of the demonstration bottle is provided with a rubber plug, a water inlet pipe and a water outlet pipe are inserted in the rubber plug, the diameter of the water inlet pipe is smaller than that of the water outlet pipe, an outlet of the water inlet pipe is close to the bottom of the demonstration bottle, a water inlet pipe section of the water outlet pipe is close to the opening of the demonstration bottle, the water inlet pipe is connected with an open water storage bottle, a water collecting bottle is arranged on the workbench and is positioned below the water outlet pipe, the water storage bottle is arranged on a boss on the workbench, and the water collecting bottle is arranged on the surface of