A novel water electrolysis experimental teaching device and its use method

Abstract

The present invention relates to a novel electrolysis water experiment teaching device and a method for using the same, comprising a base, wherein a cavity for containing an electrolyte solution is provided inside the base, a partition arranged obliquely is fixedly connected to the top surface of the cavity, the partition divides the cavity into a left cavity and a right cavity connected at the lower end, the top of the left cavity is connected to a vertically arranged water injection pipe, the top of the right cavity is fixedly connected to a vertically arranged hydrogen pipe and an oxygen pipe, and nickel-plated electrodes are respectively arranged at equal height positions at the bottom of the hydrogen pipe and the oxygen pipe, the nickel-plated electrode at the bottom of the hydrogen pipe is connected to the negative pole of a power supply, and the nickel-plated electrode at the bottom of the oxygen pipe is connected to the positive pole of a power supply. The present invention has reasonable structural design, simple operation, obvious phenomenon, can effectively solve the problems of structural instability and slow electrolysis rate existing in the current Hoffman electrolyzer, is convenient for students to group experiments, and has great promotion and application value and market prospects.

Description

Technical field:

[0002] The invention relates to a novel water electrolysis experimental teaching device and a use method thereof. Background technology:

[0004] "The Composition of Water" is the content of Topic 3 of Unit 4 of the first volume of the ninth grade chemistry textbook of the People's Education Press. The key to the teaching of this topic is to conclude that water is composed of hydrogen and oxygen elements through the facts of the water electrolysis experiment, so that students can have a deep understanding of the composition of water, help students gradually establish methods to understand the material world, and improve their core subject literacy.

[0005] The Hofmann water electrolyzer in existing textbooks has the following problems when used: (1) the center of the entire device is too high, which poses a high safety hazard when used; (2) the electrolysis rate is slow, which prolongs the teaching time. Summary of the invention:

[0007] The present invention makes improvements on the problems existing in the above-mentioned prior art, that is, the technical problem to be solved by the present invention is to provide a novel water electrolysis experimental teaching device and a use method thereof, which has a reasonable structural design, is not only stable, but also increases the electrolysis rate.

[0008] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a novel electrolysis water experiment teaching device and a method of using the same, comprising a base, wherein a cavity for containing an electrolyte solution is provided inside the base, a partition arranged obliquely is fixedly connected to the top surface of the cavity, and the partition divides the cavity into a left cavity and a right cavity connected at the lower end, the top of the left cavity is connected to a vertically arranged water injection pipe, the top of the right cavity is fixedly connected to a vertically arranged hydrogen pipe and an oxygen pipe, nickel-plated electrodes are respectively arranged at the same height positions at the bottom of the hydrogen pipe and the oxygen pipe, the nickel-plated electrode at the bottom of the hydrogen pipe is connected to the negative electrode of the power supply, and the nickel-plated electrode at the bottom of the oxygen pipe is connected to the positive electrode of the power supply.

[0009] Furthermore, the partition is in an inclined shape with a higher left end and a lower right end, and the partition is located directly below the hydrogen pipe and the oxygen pipe.

[0010] Furthermore, the inclination angle of the partition is 45°.

[0011] Furthermore, upper ends of the water injection pipe, hydrogen pipe and oxygen pipe are respectively provided with removable rubber stoppers.

[0012] Furthermore, the rubber plug at the upper end of the hydrogen pipe is connected to a hydrogen combustion assembly, which includes a glass piston with one end penetrating the rubber plug and extending into the hydrogen pipe, and the other end of the glass piston is connected to an injection needle through a rubber hose.

[0013] Furthermore, two conductive metal wires for connecting to the pulse igniter are arranged on the upper side wall of the hydrogen pipe.

[0014] Furthermore, a scale plate is vertically arranged between the hydrogen tube and the oxygen tube.

[0015] Furthermore, the base is a right-angled trapezoidal structure, and the inclination angle of the hypotenuse of the base is 76°.

[0016] Another technical solution adopted by the present invention is: a method for using a novel water electrolysis experimental teaching device, comprising the following steps:

[0017] Step S1: injecting sodium hydroxide solution into the cavity through the water injection pipe, and plugging the rubber stoppers on the water injection pipe, the hydrogen pipe and the oxygen pipe;

[0018] Step S2: Flip the base backwards until the water injection pipe, hydrogen pipe and oxygen pipe are in a horizontal state, then shake the base left and right so that the sodium hydroxide solution fills the hydrogen pipe and oxygen pipe, and then place the base to the initial state so that the water injection pipe, hydrogen pipe and oxygen pipe are in a vertical state;

[0019] Step S3: Turn on the power supply, energize the nickel-plated electrodes at the bottom of the hydrogen tube and the oxygen tube to decompose water, and observe that gas is generated in the hydrogen tube and the oxygen tube;

[0020] Step S4: Open the rubber plugs on the upper ports of the hydrogen tube and the oxygen tube in turn, insert a burning stick into the hydrogen tube and a stick with sparks into the oxygen tube, and check the gas generated by electrolysis:

[0021] Step S5: rotating the glass piston to control the flow rate of hydrogen, and igniting the hydrogen at the injection needle, placing a dry and cold test tube above the flame, and water droplets appear on the inner wall of the test tube, proving that water is composed of hydrogen and oxygen elements;

[0022] Step S6: Tilt the base so that the oxygen in the oxygen tube enters the hydrogen tube and mixes with the hydrogen, and perform a hydrogen explosion test in the hydrogen tube:

[0023] Step S61: Open the rubber plug on the upper end of the hydrogen pipe, insert a burning stick into the hydrogen pipe, and hear a sharp explosion, indicating that the hydrogen explodes;

[0024] Step S62: Connect the pulse igniter to the two conductive metal wires on the upper side wall of the hydrogen pipe. The two conductive metal wires generate sparks in the hydrogen pipe to directly detonate the mixed gas in the hydrogen pipe, causing the mixed gas to explode.

[0025] Compared with the prior art, the present invention has the following effects: the present invention has reasonable structural design, simple operation, obvious phenomenon, can effectively solve the problems existing in the current Hofman electrolyzer, can also realize gas mixing and hydrogen explosion experiments, is convenient for students to conduct group experiments, and has great promotion and application value and market prospects. Description of the drawings:

[0027] Figure 1 is a schematic diagram of the main structure of an embodiment of the present invention;

[0028] Figure 2 is a schematic diagram of a top view of the structure of an embodiment of the present invention;

[0029] Figure 3 is a right view structural schematic diagram of an embodiment of the present invention;

[0030] Figure 4 It is a schematic diagram of the structure of the hydrogen combustion component in an embodiment of the present invention.

[0031] In the figure:

[0032] 1-base; 2-partition; 3-left chamber; 4-right chamber; 5-water injection pipe; 6-hydrogen pipe; 7-oxygen pipe; 8-nickel-plated electrode; 9-rubber plug; 10-conductive metal wire; 11-rubber hose; 12-injection needle; 13-glass piston; 14-scale plate. Specific implementation method:

[0034] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] like Figures 1 to 3 As shown, a novel electrolysis water experiment teaching device of the present invention comprises a base 1, wherein a cavity for containing electrolyte solution is provided inside the base 1, and a partition plate 2 arranged obliquely is fixedly connected to the top surface of the cavity, and the partition plate 2 divides the cavity into a left cavity 3 and a right cavity 4 connected at the lower end, and the top of the left cavity 3 is connected with a vertically arranged water injection pipe 5, and the water injection pipe 5 is used to inject electrolyte solution, which can play a role in regulating pressure, and the top of the right cavity 4 is fixedly connected with a vertically arranged hydrogen pipe 6 and an oxygen pipe 7, and the hydrogen pipe 6 is located between the water injection pipe 5 and the oxygen pipe 7, and L-shaped nickel-plated electrodes 8 are respectively arranged at the same height position at the bottom of the hydrogen pipe 6 and the oxygen pipe 7, and the nickel-plated electrode 8 at the bottom of the hydrogen pipe 6 is connected to the negative electrode of the power supply, and the nickel-plated electrode 8 at the bottom of the oxygen pipe 7 is connected to the positive electrode of the power supply. Since the nickel-plated electrode has strong conductivity, the electrolysis reaction rate is greatly improved, and the nickel alloy electrode is not easily oxidized by the electrolyte and has high durability.

[0036] In this embodiment, the upper ends of the water injection pipe, hydrogen pipe and oxygen pipe are respectively provided with removable rubber plugs. By opening and tightening the rubber plugs, the gas pressure difference in the left cavity, the hydrogen pipe and the oxygen pipe can be controlled, thereby achieving the effect of controlling the height of the electrolyte solution in the hydrogen pipe and the oxygen pipe.

[0037] In this embodiment, the partition 2 is inclined with the left end higher and the right end lower, and the partition 2 is located directly below the hydrogen pipe 6 and the oxygen pipe 7. The partition 2 can effectively isolate the liquid in the hydrogen pipe 6 and the oxygen pipe 7 from the external air, ensuring the smooth progress of the electrolysis reaction. The operation of injecting the electrolyte solution into the hydrogen pipe and the oxygen pipe is as follows: inject the electrolyte solution into the cavity through the water injection pipe 5, then plug the rubber plugs 9 at the upper ends of the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7, flip the base backward until the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7 are in a horizontal state, then shake the base 1 left and right to make the sodium hydroxide solution fill the hydrogen pipe 6 and the oxygen pipe 7, and then place the base to the initial state. At this time, the right cavity and the hydrogen pipe and the oxygen pipe are all filled with electrolyte solution, and the nickel-plated electrodes at the lower ends of the hydrogen pipe and the oxygen pipe are immersed in the electrolyte solution, and the gas originally in the hydrogen pipe and the oxygen pipe is discharged to the upper end of the water injection pipe and the left cavity, that is, the two ends of the hydrogen pipe and the oxygen pipe are equivalent to vacuuming, and the hydraulic pressure of the electrolyte solution in the whole device is smaller than the atmospheric pressure, so the liquid level in the hydrogen pipe and the oxygen pipe will not drop.

[0038] In this embodiment, the base 1, the partition 2, the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7 are all made of acrylic.

[0039] In this embodiment, the rubber plug 9 at the upper end of the hydrogen pipe 6 is connected to a hydrogen combustion component, such as Figure 4 As shown, the hydrogen combustion assembly includes a glass piston 13 with one end penetrating a rubber stopper 9 and then extending into the hydrogen pipe, and the other end of the glass piston 13 is connected to an injection needle 12 through a rubber hose 11; by controlling the glass piston, the flow rate of hydrogen can be manually controlled to achieve more stable and continuous combustion of hydrogen. Preferably, the injection needle is made of stainless steel; the stainless steel needle replaces the glass tip in the existing Hoffman electrolysis device, avoiding the problem of tube mouth deformation.

[0040] In this embodiment, two conductive metal wires 10 for connecting to the pulse igniter are provided on the upper side wall of the hydrogen pipe 6; preferably, the spacing between the two conductive metal wires 10 is about 2 mm. When the pulse igniter is connected, pressing the pulse igniter switch can generate an electric spark between the two metal wires, which can ignite the mixed gas in the hydrogen pipe, causing it to explode and flush the rubber plug with a sharp bang, thereby achieving a hydrogen explosion, and the explosion phenomenon is very obvious.

[0041] In this embodiment, a scale plate 14 is vertically provided between the hydrogen tube 6 and the oxygen tube 7 for observing the volume ratio of the gases in the two tubes during electrolysis, which can intuitively reflect that the volume ratio of hydrogen and oxygen during electrolysis is 2:1.

[0042] In this embodiment, the lengths of the hydrogen pipe 6 and the oxygen pipe 7 are the same, and are both longer than the length of the water injection pipe 5 .

[0043] In this embodiment, the base 1 is a right-angled trapezoidal structure, and the hypotenuse angle of the base 1 is 76°; the upper and lower surfaces of the base are both rectangular and parallel, the front and rear surfaces of the base are both trapezoidal and parallel, the left side and the right side are also rectangular, and the left side is not parallel to the right side. Preferably, the volume of the inner cavity of the base is about 500 ml, so that enough electrolyte solution can be loaded, and the overall center of gravity of the device can be lowered, and the placement is more stable.

[0044] In this embodiment, the inclination angle of the partition 2 is 45°. When the entire device is inclined along the hypotenuse of the base of the right-angle trapezoidal structure (the inclination angle of the hypotenuse is 76°), oxygen can be guided smoothly into the hydrogen pipe, making the mixing operation of oxygen and hydrogen simple and efficient.

[0045] In this embodiment, when in use, sodium hydroxide solution is injected into the cavity through the water injection pipe 5, and then the rubber plugs 9 on the upper ends of the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7 are plugged tightly, and the base 1 is flipped backwards until the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7 are in a horizontal state, and then the base 1 is shaken left and right so that the sodium hydroxide solution fills the hydrogen pipe 6 and the oxygen pipe 7, and then the base 1 is placed to the initial state so that the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7 are in a vertical state, and finally the power is turned on, and the nickel-plated electrodes at the bottom of the hydrogen pipe and the oxygen pipe are energized to decompose water, and it is observed that gas is generated in the hydrogen pipe and the oxygen pipe, and then gas inspection, gas ignition and other operations are performed.

[0046] The advantages of the present invention are:

[0047] (1) Enlarge the base, lower the height of the hydrogen pipe and the oxygen pipe, lower the center of gravity, make it more stable, and eliminate safety hazards;

[0048] (2) Changing the electrode material and electrolyte solution to increase the electrolysis rate;

[0049] (3) Use a stainless steel needle to replace the glass tube of the original device to avoid the problem of deformation of the glass tube mouth;

[0050] (4) It is convenient to verify hydrogen or oxygen, and the phenomenon is very obvious;

[0051] (5) This device can be used to understand the composition of water from multiple perspectives. It can be used to prove the composition of water by using the "division method" of decomposing water, and it can also be used to prove the composition of water by using the "legal method" of synthesizing water, which expands students' thinking about the composition of matter.

[0052] The innovation of the present invention is to highlight the two words "interest" and "synthesis". By using the baffle in the device, students can understand the composition of water with a "synthetic" mindset in a very interesting explosion experiment, which is impossible to achieve with the traditional Hoffman device. The specific operation process includes the following steps:

[0053] Step S1: inject 500 ml of 5% sodium hydroxide solution into the cavity through the water injection pipe 5, and plug the rubber plugs 9 on the upper ends of the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7;

[0054] Step S2: Flip the base 1 backward until the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7 are in a horizontal state, then shake the base 1 left and right so that the sodium hydroxide solution fills the hydrogen pipe 6 and the oxygen pipe 7, and then place the base 1 to the initial state so that the water injection pipe 5, the hydrogen pipe 6 and the oxygen pipe 7 are in a vertical state;

[0055] Step S3: Connect a 12V DC power supply, and energize the nickel-plated electrodes at the bottom of the hydrogen tube 6 and the oxygen tube 7 to decompose water. After 30 seconds, it can be clearly observed that the volume ratio of the gas generated in the positive tube and the negative tube is 1:2;

[0056] Step S4, checking the gas generated by electrolysis: when the hydrogen generated by electrolysis is at the 5 cm scale line of the scale plate 14, the rubber plugs 9 on the upper ports of the hydrogen tube 6 and the oxygen tube 7 are opened in sequence, and the burning wooden stick is directly inserted into the hydrogen tube. The gas burns and emits a "puff" sound, which proves that the gas is hydrogen; the wooden stick with sparks is inserted into the anode tube, and the wooden stick re-ignites, which proves that the gas is oxygen; this is a method of decomposing water by electrolysis to prove that water is composed of hydrogen and oxygen elements;

[0057] Step S5, ignite the pure hydrogen in the hydrogen tube: open the rubber stopper 9 of the hydrogen tube 6, collect the hydrogen in half of the tube first, then rotate the glass piston 13 to control the flow rate of the hydrogen, and ignite the hydrogen at the injection needle 12, cover a dry and cold test tube above the flame, and find that water droplets are generated on the inner wall of the test tube, which is a method of synthesizing water by burning hydrogen to prove that water is composed of hydrogen and oxygen elements;

[0058] Step S6, mixing hydrogen and oxygen to make them explode: first collect hydrogen at a scale of 2 cm and oxygen at a scale of 1 cm, then tilt the base 1 so that the oxygen in the oxygen tube 7 enters the hydrogen tube 6 and mixes with the hydrogen, and conduct a hydrogen explosion test in the hydrogen tube 6:

[0059] Step S61, open flame detonation: open the rubber plug 9 at the upper end of the hydrogen pipe 6, insert a burning wood stick into the hydrogen pipe 6, and hear a sharp explosion sound, indicating that the hydrogen explodes;

[0060] Step S62, closed electric spark detonation: connect the pulse igniter to the two conductive metal wires 10 on the upper side wall of the hydrogen pipe 6, the two conductive metal wires 10 generate sparks in the hydrogen pipe 6, directly detonate the mixed gas in the hydrogen pipe 6, and cause the mixed gas to explode.

[0061] In summary, this device is cleverly designed and easy to operate, which is convenient for teachers to demonstrate and students to conduct group experiments. The electrolysis rate is significantly accelerated, making the traditional "division method" to prove the composition of water more efficient; using this set of devices, the "legal" method to prove the composition of water is cleverly demonstrated in an explosive way, making the "legal" teaching more interesting; using the same set of devices, using two methods to prove the composition of water, students' thinking is more profound. As chemistry learning continues to deepen, students can still understand the structure, properties and changes of substances from multiple perspectives, and learn to understand this colorful material world from a multi-faceted perspective.

[0062] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A novel water electrolysis experimental teaching device, characterized in that: The invention comprises a base, wherein a cavity for containing an electrolyte solution is provided inside the base, a partition arranged obliquely is fixedly connected to the top surface of the cavity, the partition divides the cavity into a left cavity and a right cavity which are connected at the lower end, the top of the left cavity is connected to a vertically arranged water injection pipe, the top of the right cavity is fixedly connected to a vertically arranged hydrogen pipe and an oxygen pipe, the bottoms of the hydrogen pipe and the oxygen pipe are respectively provided with nickel-plated electrodes at the same height, the nickel-plated electrode at the bottom of the hydrogen pipe is connected to the negative electrode of the power supply, and the nickel-plated electrode at the bottom of the oxygen pipe is connected to the positive electrode of the power supply; The partition is in an inclined shape with a higher left end and a lower right end, and the partition is located directly below the hydrogen pipe and the oxygen pipe; The inclination angle of the partition is 45°; The base is a right-angle trapezoidal structure, and the inclination angle of the hypotenuse of the base is 76°.

2. A novel water electrolysis experimental teaching device according to claim 1, characterized in that: The upper ends of the water injection pipe, the hydrogen pipe and the oxygen pipe are respectively provided with detachable rubber plugs.

3. A novel water electrolysis experimental teaching device according to claim 2, characterized in that: The rubber plug at the upper end of the hydrogen pipe is connected to a hydrogen combustion assembly, which includes a glass piston with one end penetrating the rubber plug and extending into the hydrogen pipe, and the other end of the glass piston is connected to an injection needle through a rubber hose.

4. A novel water electrolysis experimental teaching device according to claim 1, characterized in that: The upper side wall of the hydrogen pipe is provided with two conductive metal wires for connecting with the pulse igniter.

5. A novel water electrolysis experimental teaching device according to claim 1, characterized in that: A scale plate is vertically arranged between the hydrogen tube and the oxygen tube.

6. A method for using a novel water electrolysis experimental teaching device, characterized in that: The method comprises adopting the novel water electrolysis experimental teaching device as claimed in any one of claims 1 to 5, comprising the following steps: Step S1: injecting sodium hydroxide solution into the cavity through the water injection pipe, and plugging the rubber stoppers on the water injection pipe, the hydrogen pipe and the oxygen pipe; Step S2: Flip the base backwards until the water injection pipe, hydrogen pipe and oxygen pipe are in a horizontal state, then shake the base left and right so that the sodium hydroxide solution fills the hydrogen pipe and oxygen pipe, and then place the base to the initial state so that the water injection pipe, hydrogen pipe and oxygen pipe are in a vertical state; Step S3: Turn on the power supply, energize the nickel-plated electrodes at the bottom of the hydrogen tube and the oxygen tube to decompose water, and observe that gas is generated in the hydrogen tube and the oxygen tube; Step S4: Open the rubber plugs on the upper ports of the hydrogen tube and the oxygen tube in turn, insert a burning stick into the hydrogen tube and a stick with sparks into the oxygen tube, and check the gas generated by electrolysis: Step S5: rotating the glass piston to control the flow rate of hydrogen, and igniting the hydrogen at the injection needle, placing a dry and cold test tube above the flame, and water droplets appear on the inner wall of the test tube, proving that water is composed of hydrogen and oxygen elements; Step S6: Tilt the base so that the oxygen in the oxygen tube enters the hydrogen tube and mixes with the hydrogen, and perform a hydrogen explosion test in the hydrogen tube: Step S61: Open the rubber plug on the upper end of the hydrogen pipe, insert a burning stick into the hydrogen pipe, and hear a sharp explosion, indicating that the hydrogen explodes; Step S62: Connect the pulse igniter to the two conductive metal wires on the upper side wall of the hydrogen pipe. The two conductive metal wires generate sparks in the hydrogen pipe to directly detonate the mixed gas in the hydrogen pipe, causing the mixed gas to explode.

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