Experimental principle demonstration device for collecting gas through air exhaust method

Abstract

The utility model relates to the technical field of teaching aids, in particular to an experimental principle demonstration device for collecting gas by an air exhaust method, which comprises a gas making device, a gas collecting device and a tail gas treatment device, the input end of the gas collecting device is communicated with the gas making device, and the output end of the gas collecting device is communicated with the tail gas treatment device. The gas making device comprises a first beaker, a dispensing bottle and a drying pipe, the first beaker is communicated with the drying pipe through a guide pipe, and the dispensing bottle is communicated with the drying pipe through a guide pipe; the gas collecting device comprises a first branch pipe, a three-way pipe and a second branch pipe, the input end of the first branch pipe is communicated with the first beaker, the output end of the first branch pipe is communicated with a first channel of the three-way pipe, and a second channel of the three-way pipe is communicated with the input end of the second branch pipe. And the change of the position of the colored gas in the branch pipe is shown, so that the principle of collecting the gas by an air exhaust method can be more intuitively observed.

Description

Technical Field

[0001] The utility model relates to the technical field of teaching tools, in particular to an experimental principle demonstration device for collecting gas by exhausting air. Background Art

[0002] The air exhaust method is a method of collecting gas. According to the specific conditions of the gas, it is divided into the upward air exhaust method and the downward air exhaust method. If the gas density is less than the air density, the downward air exhaust method is used. If the gas density is greater than the air density, the upward air exhaust method is used.

[0003] When demonstrating the air exhaust method in teaching, first fix moistened litmus papers in two gas collecting bottles, then collect carbon dioxide using the upward and downward air exhaust methods respectively. By comparing the color changes of the litmus papers in the two gas collecting bottles, the interaction between carbon dioxide and the air after entering the gas collecting bottles can be inferred. However, it does not allow the observer to directly see the actual interaction between the collected gas and the air in the original bottle. The observer is required to analyze, infer, and imagine the observed phenomena in order to have a general understanding of the interaction between the collected gas and the air in the original bottle. Utility Model Content

[0004] In view of the shortcomings of the prior art, the utility model provides an experimental principle demonstration device for collecting gas by exhausting air, which uses two vertically arranged branch pipes to show the changes in the position of the colored gas in the branch pipes, so that the principle of collecting gas by exhausting air can be observed more intuitively.

[0005] The utility model provides the following technical solutions:

[0006] The invention discloses an experimental principle demonstration device for collecting gas by exhausting air, comprising a gas making device, a gas collecting device and an exhaust gas treatment device, wherein one input end of the gas collecting device is connected to the gas making device, and the output end of the gas collecting device is connected to the exhaust gas treatment device, the gas making device comprises a first beaker, a glue dispensing bottle and a drying tube, the first beaker is connected to the drying tube through a conduit, and the glue dispensing bottle is connected to the drying tube through a conduit; the gas collecting device comprises a first branch pipe, a tee pipe and a second branch pipe, the input end of the first branch pipe is connected to the first beaker, the output end of the first branch pipe is connected to the first channel of the tee pipe, the second channel of the tee pipe is connected to the input end of the second branch pipe, and the output end of the second branch pipe is connected to the input end of the exhaust gas treatment device; the third channel of the tee pipe is connected to the air.

[0007] Furthermore, the tail gas treatment device includes a safety bottle and a second beaker, the top of the safety bottle is connected to the second branch pipe outlet, and the second beaker is connected to the second branch pipe outlet and the bottom of the safety bottle.

[0008] Furthermore, pistons are provided in the conduits between the drying tube and the first beaker, the dispensing bottle, and the first branch pipe; a piston is provided in the channel connecting the three-way pipe and the air; and a piston is provided in the conduits between the second branch pipe and the safety bottle and the second beaker.

[0009] Furthermore, it also includes a residual gas processing device, which includes a first syringe and a second syringe, the first syringe is connected to the drying tube through a conduit, and the second syringe is connected to the first branch pipe through a conduit.

[0010] Furthermore, the first beaker is filled with water.

[0011] Furthermore, the dispensing bottle is filled with concentrated nitric acid, and a copper sheet is placed at the bottom of the drying tube.

[0012] Furthermore, the second beaker is filled with sodium hydroxide solution.

[0013] The utility model has the following beneficial technical effects:

[0014] 1. The utility model uses two vertically arranged branch pipes to show the change of the position of the colored gas in the branch pipes, and the principle of collecting gas by exhausting air can be observed more intuitively.

[0015] 2. The utility model requires fewer instruments and a shorter demonstration time, and is suitable for classroom demonstration. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the utility model.

[0017] The reference numerals in the figure are as follows:

[0018] 11. first beaker; 12. dispensing bottle; 13. drying tube; 21. first branch pipe; 22. three-way pipe; 23. second branch pipe; 31. safety bottle; 32. second beaker; 41. first syringe; 42. second syringe. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0020] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0021] like Figure 1As shown, the experimental principle demonstration device for collecting gas by exhausting air in this embodiment includes a gas making device, a gas collecting device and an exhaust gas treatment device. One input end of the gas collecting device is connected to the gas making device, and the output end of the gas collecting device is connected to the exhaust gas treatment device. The gas making device includes a first beaker 11, a glue dispensing bottle 12 and a drying tube 13. The first beaker 11 is connected to the drying tube 13 through a conduit, and the glue dispensing bottle 12 is connected to the drying tube 13 through a conduit; the gas collecting device includes a first branch pipe 21, a tee pipe 22 and a second branch pipe 23. The input end of the first branch pipe 21 is connected to the first beaker 11, the output end of the first branch pipe 21 is connected to the first channel of the tee pipe 22, the second channel of the tee pipe 22 is connected to the input end of the second branch pipe 23, and the output end of the second branch pipe 23 is connected to the input end of the exhaust gas treatment device; the third channel of the tee pipe 22 is connected to the air.

[0022] The gas production device includes a dispensing bottle 12 and a drying tube 13, which are connected by a silicone tube. Nitrogen dioxide gas is produced by adding concentrated nitric acid to the drying tube 13 containing a copper sheet through the dispensing bottle 12, and the chemical equation of the reaction is Cu+4HNO3=Cu(NO3)2+2NO2↑+2H2O. When the amount of nitrogen dioxide gas required for the experiment is sufficient, the piston between the drying tube 13 and the first beaker 11 discharges the unreacted acid, and the copper is separated from the concentrated nitric acid to stop the continued generation of nitrogen dioxide.

[0023] The gas collecting device includes two branch pipes and a three-way pipe 22 connecting the two branch pipes. The first branch pipe 21, the second branch pipe 23 and the three-way pipe 22 are connected by a silicone tube. The first branch pipe 21 collects gas from bottom to top by simulating the upward air exhaust method, and the second branch pipe 23 collects gas from top to bottom by simulating the downward air exhaust method.

[0024] Furthermore, the tail gas treatment device includes a safety bottle 31 and a second beaker 32 . The top of the safety bottle 31 is connected to the outlet of the second branch pipe 23 , and the second beaker 32 is connected to the outlet of the second branch pipe 23 and the bottom of the safety bottle 31 .

[0025] The tail gas treatment device includes a safety bottle 31 and a second beaker 32 containing a sodium hydroxide solution. The tail gas treatment device has two functions: one is to absorb tail gas, and the other is to provide a sodium hydroxide solution for treating the nitrogen dioxide remaining in the first branch pipe 21 and the second branch pipe 23. When absorbing tail gas, the pistons at the second branch pipe 23 and the safety bottle 31 are opened, and the pistons at the second branch pipe 23 and the second beaker 32 are closed. The safety bottle 31 can be regarded as an extension of the branch pipe. When the gas increment is equal, the gas pressure increment is relatively small when the space occupied by the gas is large, which is conducive to the discharge of the gas in the pipe. At the same time, the nitrogen dioxide gas generated by the reaction enters the safety bottle 31 and is diluted by the air in the bottle, which is conducive to the complete absorption of nitrogen dioxide by the sodium hydroxide solution in the flow. The chemical equation of the reaction is 2NO2+2NaOH=NaNO3+NaNO2+H2O. When the reaction is finished and the nitrogen dioxide gas remaining in the branch pipe is treated, the pistons at the second branch pipe 23 and the safety bottle 31 are closed, and the pistons at the second branch pipe 23 and the second beaker 32 are opened.

[0026] Furthermore, pistons are provided in the conduits between the drying tube 13 and the first beaker 11, the dispensing bottle 12, and the first branch pipe 21; a piston is provided in the channel connecting the three-way pipe 22 and the air; and a piston is provided in the conduits between the second branch pipe 23 and the safety bottle 31 and the second beaker 32.

[0027] Furthermore, it also includes a residual gas processing device, which includes a first syringe 41 and a second syringe 42. The first syringe 41 is connected to the drying tube 13 through a conduit, and the second syringe 42 is connected to the first branch pipe 21 through a conduit.

[0028] The residual gas treatment device includes a first syringe 41 for treating the residual gas in the gas production device and a second syringe 42 for treating the residual gas in the gas collection device. The two gas cylinders are connected to the drying tube 13 and the second branch pipe 23 by silicone tubes (harder than latex tubes, and will not affect the exhaust due to decompression and closure). The method for treating the residual gas in the gas production device is: before the experiment, pull the piston of the first syringe 41 to inhale air about 1.25 times the volume of the drying tube 13. When treating the residual gas in the tube, continue to pull the piston of the first syringe 41, and inhale the gas in the drying tube 13 and the water in the first beaker 11 into the syringe in an appropriate amount, and use the reaction 4NO2+O2+2H2O=4HNO3 to remove nitrogen dioxide. The method for treating the residual gas in the gas collection device is: use the second syringe 42 to inhale the residual gas in the branch pipe and the sodium hydroxide solution in the tail gas treatment device into the second syringe 42, and the reaction is 2NO2+2NaOH=NaNO3+NaNO2+H2O.

[0029] Furthermore, the first beaker 11 is filled with water.

[0030] Furthermore, the dispensing bottle 12 is filled with concentrated nitric acid, and a copper sheet is placed at the bottom of the drying tube 13 .

[0031] Furthermore, the second beaker 32 is filled with sodium hydroxide solution.

[0032] The method of using the utility model is:

[0033] 1. Check the air tightness of the device: close the piston between the first beaker 11 and the drying tube 13, and the piston of the three-way pipe 22 connected to the air, open the remaining pistons, gently pull the first syringe 41, and the liquid level of the two tubes in the second beaker 32 will rise; push the first syringe 41 to reset it, and observe that the liquid level of the two tubes in the second beaker 32 will drop, indicating that the air tightness of the device is good.

[0034] 2. Add reagents to control the reaction: Add relevant reagents, and use the first syringe 41 to inhale about 1.5 times (theoretically 1.25 times) the volume of the drying tube 13. Close the piston between the second branch tube 23 and the second beaker 32, open the piston between the dispensing bottle 12 and the drying tube 13, raise the dispensing bottle 12 with the bottle mouth facing down, squeeze the dispensing bottle 12 to add concentrated nitric acid into the drying tube 13, and close the piston between the dispensing bottle 12 and the drying tube 13. It can be seen that the reaction between copper and concentrated nitric acid is from slow to fast, and the dark red-brown gas produced quickly fills the drying tube 13 and flows into the first branch tube 21. The dark red-brown gas fills the first branch tube 21 from bottom to top. In this process, there is a clear interface between the red-brown gas and the colorless gas (air). After the dark red-brown gas enters the second branch tube 23 through the bend, the gushing dark red-brown gas quickly mixes with the colorless gas (air), and the diluted red-brown gas soon spreads in the right tube. Open the piston between the first beaker 11 and the drying tube 13, close the piston between the first branch pipe 21 and the drying tube 13, allow the liquid in the drying tube 13 to flow into the beaker, stop the generation of gas, and close the piston between the first beaker 11 and the drying tube 13.

[0035] 3. Treat the residual gas in the drying tube 13: replace the beaker that receives the discharged concentrated nitric acid with a beaker containing water, open the piston between the first beaker 11 and the drying tube 13, pull the first syringe 41, and the gas in the drying tube 13 and the water in the first beaker 11 are successively sucked into the first syringe 41. Oscillate the first syringe 41 to allow the gas and liquid to fully contact and react. After the reddish-brown gas disappears, push the first syringe 41 to discharge the liquid and excess gas in the first syringe 41 and the drying tube 13.

[0036] 4. Treat the residual gas in the safety bottle 31: pull the piston of the second syringe 42 to allow an appropriate amount of sodium hydroxide solution to flow into the safety bottle 31, and shake the safety bottle 31 to remove nitrogen dioxide.

[0037] 5. Treat the residual gas in the branch pipe: close the piston between the second branch pipe 23 and the safety bottle 31, open the piston between the second branch pipe 23 and the second beaker 32, continue to pull the piston of the second syringe 42, the gas in the pipe is drawn into the second syringe 42, the sodium hydroxide solution flows from the second branch pipe 23 into the first branch pipe 21 and into the second syringe 42, oscillate the second syringe 42, make the gas and liquid fully contact to remove nitrogen dioxide. After such an operation, there is often some reddish-brown gas in the first branch pipe 21 that has not been removed, the gas and liquid in the second syringe 42 can be slowly pressed out, repeat the above operation 1 to 2 times, and the nitrogen dioxide in the branch pipe can be completely removed.

[0038] 6. Discharge the residual liquid in the branch pipes: open the piston between the first beaker 11 and the drying tube 13, and the piston connected to the air of the three-way pipe 22, and the liquid level in the first branch pipe 21 and the second branch pipe 23 will drop, and the solution after absorbing nitrogen dioxide will be discharged into the beakers of the first beaker 11 and the second beaker 32 respectively.

[0039] 7. Cleaning and drying of the device: Since there is residual alkali solution in the device after alkali washing, it should be cleaned as a whole for safety reasons. The first syringe 41 and the second syringe 42 are used to draw air at the lower ends of the first branch pipe 21 and the second branch pipe 23 to draw water into the first branch pipe 21 and the second branch pipe 23 to the middle three-way pipe 22 to achieve cleaning. If necessary, they can be disassembled and cleaned separately. Considering that the drying tube 13, branch pipes and their catheters, syringes, etc. used in this experiment must be dried, in order to quickly dry the cleaned instruments, they should be disassembled and dried separately, and can also be dried if needed urgently.

[0040] The above-mentioned embodiments only express the specific implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model.

Claims

1. An experimental principle demonstration device for collecting gas by exhausting air, comprising a gas making device, a gas collecting device and an exhaust gas treatment device, wherein the input end of the gas collecting device is connected to the gas making device, and the output end of the gas collecting device is connected to the exhaust gas treatment device, characterized in that: The gas production device comprises a first beaker (11), a glue dispensing bottle (12) and a drying tube (13); the first beaker (11) is connected to the drying tube (13) through a conduit, and the glue dispensing bottle (12) is connected to the drying tube (13) through a conduit; the gas collection device comprises a first branch pipe (21), a three-way pipe (22) and a second branch pipe (23); the input end of the first branch pipe (21) is connected to the first beaker (11), the output end of the first branch pipe (21) is connected to the first channel of the three-way pipe (22), the second channel of the three-way pipe (22) is connected to the input end of the second branch pipe (23), and the output end of the second branch pipe (23) is connected to the input end of the tail gas treatment device; the third channel of the three-way pipe (22) is connected to the air.

2. The experimental principle demonstration device for collecting gas by exhausting air according to claim 1 is characterized in that: The tail gas treatment device comprises a safety bottle (31) and a second beaker (32). The top of the safety bottle (31) is connected to the outlet of the second branch pipe (23), and the second beaker (32) is connected to the outlet of the second branch pipe (23) and the bottom of the safety bottle (31).

3. The experimental principle demonstration device for collecting gas by exhausting air according to claim 2 is characterized in that: The conduits between the drying tube (13) and the first beaker (11), the dispensing bottle (12), and the first branch pipe (21) are all provided with pistons; the passage between the three-way pipe (22) and the air is provided with a piston; and the conduits between the second branch pipe (23) and the safety bottle (31) and the second beaker (32) are all provided with pistons.

4. The experimental principle demonstration device for collecting gas by exhausting air according to claim 1 is characterized in that: It also includes a residual gas processing device, which includes a first syringe (41) and a second syringe (42). The first syringe (41) is connected to the drying tube (13) through a conduit, and the second syringe (42) is connected to the first branch pipe (21) through a conduit.

5. The experimental principle demonstration device for collecting gas by exhausting air according to claim 1 is characterized in that: The first beaker (11) is filled with water.

6. The experimental principle demonstration device for collecting gas by exhausting air according to claim 1 is characterized in that: The dispensing bottle (12) is filled with concentrated nitric acid, and a copper sheet is placed at the bottom of the drying tube (13).

7. The experimental principle demonstration device for collecting gas by exhausting air according to claim 1 is characterized in that: The second beaker (32) contains sodium hydroxide solution.

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