Integrated experimental device and method for combustion of hydrogen in chlorine

Abstract

An integrated experimental device and method for hydrogen combustion in chlorine, a support is provided with a conical flask located above a combustion nozzle, a sponge pad is provided in the conical flask, a first test tube, a second test tube, and a third test tube are respectively provided on the support through a clip, a sponge strip is provided in the first test tube, the first test tube is connected to the second test tube through a three-way conduit provided with a three-way valve, an air outlet pipe is provided on the rubber plug cover at the upper end of the first test tube, the second test tube is connected to the combustion nozzle through the three-way conduit, the second test tube is connected to the third test tube through a conduit, and the third test tube is connected to a one-way inflation ball through a conduit. The present invention adopts the hydrogen generated by the reaction of the hydrogen generating device to enter the inner tube and the chlorine generated by the reaction of the chlorine generating device to enter the combustion nozzle to generate a combustion reaction, so that the preparation of hydrogen and chlorine and the combustion experiment of hydrogen in chlorine can be carried out in a closed space, avoiding the escape of harmful gases, and effectively solving the problem of environmental pollution caused by the experiment.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical experimental equipment, and in particular relates to an integrated experimental device and method for burning hydrogen in chlorine. Background Art

[0002] In the middle school chemistry textbook, "Hydrogen combustion experiment in chlorine" is an important classic classroom demonstration experiment. General secondary chemistry textbooks adopt a method, that is, after igniting hydrogen, insert it into a gas collecting bottle filled with chlorine. Hydrogen burns quietly in chlorine, and observes the color of the flame and its experimental phenomena. Although the experimental method in the textbook has obvious phenomena, it has many shortcomings: First, chlorine is usually prepared by heating concentrated hydrochloric acid and manganese dioxide. Since concentrated hydrochloric acid easily volatilizes a large amount of hydrogen chloride gas under heating conditions, the impurities contained in the product chlorine will interfere with the combustion experiment; second, the hydrogen and chlorine required for combustion require a complex preparation system, which has problems such as large consumption of reactants and inconvenient loading, unloading and cleaning; third, when hydrogen burns in chlorine, the chlorine in the bottle and the hydrogen chloride gas generated during combustion are easy to escape from the mouth of the gas collecting bottle, which will cause indoor environmental pollution. These problems have brought great difficulties to experimental teaching, increased the workload of experimental preparation, and are not in line with the concept of green chemistry and environmental protection.

[0003] In response to the above situation, we have improved the experimental instruments and equipment, and researched and designed an integrated experimental device and method for the combustion of hydrogen in chlorine. The improved experimental device enables the production of hydrogen and chlorine and the combustion of hydrogen in chlorine to be carried out in a closed space, avoiding the escape of harmful gases, effectively solving the problem of environmental pollution caused by the experiment, and overcoming the shortcomings in the textbooks and related improved experiments. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the disadvantages of the above-mentioned prior art and provide an integrated experimental device and method for the combustion of hydrogen in chlorine, which improves the operability of the experiment of combustion of hydrogen in chlorine, avoids the escape of harmful gases, and reduces pollution and reagent consumption.

[0005] The technical solution adopted to solve the above technical problems is: a liquid storage cup is arranged on the bracket, a liquid reaction reagent is contained in the liquid storage cup, the liquid storage cup is connected to the receiving device through a flow regulator, a reactor located below the receiving device is arranged on the bracket through a clamp, a sieve plate is arranged in the reactor, a solid reaction reagent is arranged on the sieve plate, an air pressure balance pipe is arranged on the reactor, a drain valve is arranged at the bottom of the reactor, a beaker located below the reactor is arranged on the base, a combustion nozzle is arranged on the bracket through a clamp, the receiving device is connected to the inner tube arranged in the combustion nozzle through an air guide pipe, and a gas pressure balance pipe is arranged on the bracket above the combustion nozzle. A conical flask is provided with a sponge pad in the conical flask, a first test tube, a second test tube and a third test tube are respectively provided on the bracket through clips, the upper ends of the first test tube, the second test tube and the third test tube are respectively provided with rubber plug covers, a sponge strip is provided in the first test tube, the first test tube is connected with the second test tube through a three-way conduit provided with a three-way valve, an air outlet pipe is provided on the rubber plug cover at the upper end of the first test tube, the second test tube is connected with the combustion nozzle through the three-way conduit, the second test tube is connected with the third test tube through the conduit, a rubber-tipped dropper is provided on the rubber plug cover at the upper end of the third test tube, and the third test tube is connected with the one-way inflation ball through the conduit.

[0006] The method using the above experimental setup consists of the following steps:

[0007] (1) Preparation of hydrogen and hydrogen purity test

[0008] Open the flow regulator and adjust the dripping rate of the sulfuric acid solution in the storage cup to 2-3 drops / second. The sulfuric acid solution reacts with the zinc particles to produce hydrogen. The hydrogen is collected into a test tube by the drainage method. The hydrogen is tested for purity by placing it close to the flame of an alcohol lamp. When the hydrogen is ignited, a sharp explosion sound indicates that the gas is impure, and a small sound indicates that the gas is pure. After the test, the generated hydrogen enters the inner tube through the air guide tube and ignites the hydrogen at the gas outlet of the combustion nozzle.

[0009] (2) Preparation of chlorine

[0010] Open the three-way valve on the three-way conduit to connect the second test tube to the combustion nozzle through the three-way conduit, close the connection between the first test tube and the three-way conduit, drop 2-3 mL of concentrated hydrochloric acid in a rubber-tipped dropper into the third test tube, react with potassium permanganate in the third test tube to produce chlorine, squeeze the one-way inflation balloon to blow the gas out of the third test tube, collect it above the saturated salt water solution in the second test tube, and wait for it to react with hydrogen;

[0011] (3) Combustion of hydrogen in chlorine

[0012] The chlorine gas produced in the reaction of step (2) enters the combustion nozzle and undergoes a combustion reaction with the hydrogen ignited in step (1). The blue flame turns pale and white smoke is observed to be generated in the conical flask.

[0013] (4) Inspection product

[0014] Close the flow regulator, open the three-way valve on the three-way conduit, close the connection between the second test tube and the combustion nozzle, and connect the first test tube to the combustion nozzle through the three-way conduit. After the reaction is completed, take out the sponge pad in the conical flask, drop the remaining liquid in the conical flask on the blue litmus paper, and the test paper changes from blue to red, proving that the product is acidic. Add drops of silver nitrate solution to the conical flask to produce a white precipitate insoluble in dilute nitric acid, proving that the product is hydrogen chloride.

[0015] The present invention adopts the method that the hydrogen generated by the reaction of the hydrogen generator enters the inner tube and the chlorine generated by the reaction of the chlorine generator enters the combustion nozzle to generate a combustion reaction, and the color of the flame and the experimental phenomenon are observed in the conical flask, so that the preparation of hydrogen and chlorine and the combustion experiment of hydrogen in chlorine are carried out in a closed space, and the escape of harmful gases is avoided, which effectively solves the problem of environmental pollution caused by the experiment, can improve the operability of the combustion experiment of hydrogen in chlorine, is conducive to classroom demonstration, is convenient for students to operate by hand, improves the teaching quality, and can achieve intuitive, vivid, lively and interesting teaching effects in the teaching process. The present invention has the advantages of low cost, easy preparation, and simple and easy operation. The present invention is suitable for experimental devices of ammonia combustion experiment in oxygen, acetylene combustion experiment in oxygen, hydrogen sulfide combustion experiment in oxygen, sulfur dioxide gas and hydrogen sulfide gas reaction, ammonia and hydrogen chloride gas reaction, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] like Figure 1 As shown, the integrated experimental device for combustion of hydrogen in chlorine of this embodiment is composed of a liquid storage cup 1, a conical flask 2, a sponge pad 3, an inner tube 4, a combustion nozzle 5, a three-way valve 6, a three-way conduit 7, a bracket 8, a rubber-tipped dropper 9, a clip 10, a base 11, a one-way inflation ball 12, a third test tube 13, a second test tube 14, an air outlet pipe 15, a first test tube 16, a sponge strip 17, a beaker 18, a drain valve 19, a reactor 20, a sieve plate 21, an air pressure balance pipe 22, a solid reaction reagent 23, a transfer device 24, an air guide pipe 25, a flow regulator 26, and a liquid reaction reagent 27.

[0019] A liquid storage cup 1 is installed in the hole of the upper end plate of the bracket 8. The liquid storage cup 1 contains a liquid reaction reagent 27, which is a 20% H2SO4 solution. The liquid storage cup 1 is connected to the receiver 24 through a flow regulator 26. The flow regulator 26 can control the dripping speed of the reaction liquid and adjust the gas generation speed. A reactor 20 located below the receiver 24 is mounted on the bracket 8 by means of a clip 10, a sieve plate 21 is mounted in the reactor 20, a solid reaction reagent 22 is mounted on the sieve plate 21, and the solid reaction reagent 22 is zinc particles immersed in a CuSO4 solution, an air pressure balance pipe 22 is mounted on the reactor 20, a drain valve 19 is mounted at the bottom of the reactor 20, a beaker 18 located below the reactor 20 is placed on the base 11, and the upper and lower air pressures are balanced between the reactor 20 above the sieve plate 21 and the reactor 20 below the sieve plate 21 by means of the air pressure balance pipe 22, and when the liquid level in the reactor 20 below the sieve plate 21 is higher than the lower port of the air pressure balance pipe 22, the drain valve 19 is opened to discharge the waste liquid into the beaker 18. A combustion nozzle 5 is installed on the bracket 8 through a clip 10, a transfer device 24 is connected to the inner tube 4 through an air guide tube 25, the inner tube 4 is installed in the combustion nozzle 5, a conical flask 2 is installed in another hole of the upper end plate of the bracket 8, and a sponge pad 3 moistened with distilled water is placed in the conical flask 2. The bracket 8 is respectively installed with a first test tube 16, a second test tube 14, and a third test tube 13 through the clip 10. The upper ends of the first test tube 16, the second test tube 14, and the third test tube 13 are respectively covered with rubber plugs. The first test tube 16 is filled with 20% NaOH solution and a sponge strip 17 soaked in NaOH solution is evenly filled on the upper part of the liquid surface. The sponge strip 17 and the NaOH solution can better absorb the exhaust gas. The first test tube 16 is connected to the second test tube 14 through a three-way conduit 7, a three-way valve 6 is installed on the three-way conduit 7, an air outlet pipe 15 is installed on the rubber plug cover at the upper end of the first test tube 16, the second test tube 14 is connected to the combustion nozzle 5 through the three-way conduit 7, and the second test tube 14 is filled with saturated salt water, which can remove hydrogen chloride gas in the gas without consuming chlorine and purify chlorine. The second test tube 14 is connected to the third test tube 13 through a conduit, a rubber-tipped dropper 9 is provided on the rubber plug cover at the upper end of the third test tube 13, and the third test tube 13 is connected to the one-way inflation ball 12 through a conduit, and potassium permanganate powder is installed in the third test tube 13, and the one-way inflation ball 12 is used to inflate the chlorine produced in the third test tube 13 to ensure that the chlorine does not leak.

[0020] The operation steps of this embodiment are as follows:

[0021] (1) Preparation of hydrogen and hydrogen purity test

[0022] Open the flow regulator 26, adjust the dripping rate of the sulfuric acid solution in the liquid storage cup 1 to 2-3 drops / second, the sulfuric acid solution reacts with the zinc particles to generate hydrogen, the hydrogen is collected into a test tube by the drainage method, and the hydrogen is tested for purity near the flame of the alcohol lamp. When the hydrogen is ignited, a sharp explosion sound indicates that the gas is impure, and a small sound indicates that the gas is pure. After the purity is tested, the generated hydrogen enters the inner tube 4 through the air guide tube 25 and ignites the gas outlet of the combustion nozzle 5;

[0023] (2) Preparation of chlorine

[0024] Open the three-way valve 6 on the three-way conduit 7, connect the second test tube 14 with the combustion nozzle 5 through the three-way conduit 7, close the connection between the first test tube 16 and the three-way conduit 7, drop 2-3 mL of concentrated hydrochloric acid in the rubber-tipped dropper 9 into the third test tube 13, react with the potassium permanganate in the third test tube 13 to produce chlorine, squeeze the one-way inflation ball 12, blow the gas out of the third test tube 13, collect it above the saturated salt water solution in the second test tube 14, and wait for it to react with hydrogen;

[0025] (3) Combustion of hydrogen in chlorine

[0026] The chlorine gas produced by the reaction in step 2 enters the combustion nozzle 5 and reacts with the hydrogen ignited in step 1. The blue flame turns pale, and white smoke is observed to be generated in the conical flask 2.

[0027] (4) Inspection product

[0028] Close the flow regulator 26, open the three-way valve 6 on the three-way conduit 7, close the connection between the second test tube 14 and the combustion nozzle 5, and connect the first test tube 16 to the combustion nozzle 5 through the three-way conduit 7. After the reaction is completed, take out the sponge pad 3 in the conical flask 2, drop the residual liquid in the conical flask 2 on the blue litmus paper, and the test paper changes from blue to red, which proves that the product is acidic. Add drops of silver nitrate solution to the conical flask 2 to produce a white precipitate insoluble in dilute nitric acid, which proves that the product is hydrogen chloride.

[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention.

Claims

1. An experimental method for combustion of hydrogen in chlorine, characterized in that The experimental device comprises: a liquid storage cup (1) is arranged on a support (8), a liquid reaction reagent (27) is contained in the liquid storage cup (1), the liquid storage cup (1) is connected to a receiving device (24) through a flow regulator (26), a reactor (20) is arranged on the support (8) through a clamp (10) and is located below the receiving device (24), a sieve plate (21) is arranged in the reactor (20), a solid reaction reagent (23) is contained on the sieve plate (21), a gas pressure balance pipe (22) is arranged on the reactor (20), a drain valve (19) is arranged at the bottom of the reactor (20), and a beaker (18) is arranged on the base (11) and is located below the reactor (20), characterized in that: a combustion nozzle (5) is arranged on the support (8) through a clamp (10), the receiving device (24) is connected to an inner tube (4) arranged in the combustion nozzle (5) through an air guide tube (25), and a gas pressure balance pipe (22) is arranged on the reactor (20). 5) a conical flask (2) at the top, a sponge pad (3) is arranged in the conical flask (2), a first test tube (16), a second test tube (14), and a third test tube (13) are arranged on the bracket (8) through a clamp (10), and rubber plugs are arranged on the upper ends of the first test tube (16), the second test tube (14), and the third test tube (13), respectively. A sponge strip (17) is arranged in the first test tube (16), and the first test tube (16) is provided with a three-way valve (6) The three-way conduit (7) is connected to the second test tube (14); the rubber plug cover at the upper end of the first test tube (16) is provided with an air outlet pipe (15); the second test tube (14) is connected to the combustion nozzle (5) through the three-way conduit (7); the second test tube (14) is connected to the third test tube (13) through the conduit; the rubber plug cover at the upper end of the third test tube (13) is provided with a rubber-tipped dropper (9); the third test tube (13) is connected to the one-way inflation ball (12) through the conduit; The experimental method using the above experimental setup consists of the following steps: (1) Preparation of hydrogen and hydrogen purity test The flow regulator (26) is turned on to adjust the dripping rate of the sulfuric acid solution in the storage cup (1) to 2 to 3 drops / second. The sulfuric acid solution reacts with the zinc particles to generate hydrogen. The hydrogen is collected in a test tube by a drainage method. The hydrogen is tested for purity by placing it close to the flame of an alcohol lamp. When the hydrogen is ignited, a sharp explosion sound indicates that the gas is impure, while a small sound indicates that the gas is pure. After the test, the generated hydrogen enters the inner tube (4) through the gas guide tube (25) and ignites the hydrogen at the gas outlet of the combustion nozzle (5); (2) Preparation of chlorine Open the three-way valve (6) on the three-way conduit (7) to connect the second test tube (14) to the combustion nozzle (5) through the three-way conduit (7), close the connection between the first test tube (16) and the three-way conduit (7), drop 2-3 mL of concentrated hydrochloric acid in the rubber-tipped dropper (9) into the third test tube (13), react with the potassium permanganate in the third test tube (13) to produce chlorine gas, squeeze the one-way inflation balloon (12), blow the gas out of the third test tube (13), collect it above the saturated salt water solution in the second test tube (14), and wait for it to react with hydrogen gas; (3) Combustion of hydrogen in chlorine The chlorine gas produced in the reaction of step (2) enters the combustion nozzle (5) and undergoes a combustion reaction with the hydrogen ignited in step (1), the blue flame turns pale, and white smoke is observed to be generated in the conical flask (2); (4) Product inspection The flow regulator (26) is closed, the three-way valve (6) on the three-way conduit (7) is opened, the connection between the second test tube (14) and the combustion nozzle (5) is closed, and the first test tube (16) is connected to the combustion nozzle (5) through the three-way conduit (7). After the reaction is completed, the sponge pad (3) in the conical flask (2) is taken out, and the residual liquid in the conical flask (2) is dripped onto the blue litmus paper. The test paper changes from blue to red, indicating that the product is acidic. A drop of silver nitrate solution is added to the conical flask (2), and a white precipitate insoluble in dilute nitric acid is generated, indicating that the product is hydrogen chloride.

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