Galvanic cell electromotive force measuring device for common chemical experiment

Abstract

The utility model discloses a primary battery electromotive force measuring device for a common chemical experiment. According to the primary battery electromotive force measuring device, the reaction container with the clamping groove is designed, the electrode plate can be inserted into the clamping groove to be fixed, meanwhile, the electrode plate can move up and down along the clamping groove to be disassembled and assembled, and a pole piece can be fixed on the electrode plate through a screw when electromotive force is measured. The stability and the accuracy of data during electromotive force testing are ensured; the inner shell cover on the arranged metal inner shell can be opened, and after the reaction container is taken out, the addition of an electrolyte solution in the reaction container and the installation of a pole piece can be directly completed outside the device, so that the assembly of a primary battery is convenient, and the experiment efficiency is improved; the arrangement of the metal shell reduces the contact degree of the electrolyte solution and air. According to the device, the voltmeter, the pole piece, the electrolyte solution, the salt bridge and the like are integrated, so that the operation safety and the experiment efficiency are greatly improved. When the device is used for measuring the electromotive force of the primary battery, the relative error is below 2%.

Description

TECHNICAL FIELD

[0001] The utility model belongs to ordinary chemical experiment instrument technical field relates to a primary cell electromotive force measuring device for ordinary chemical experiment. BACKGROUND

[0002] The primary cell is a device that converts the chemical energy of redox reaction into electric energy. It is generally composed of two electrodes, electrolyte solution and salt bridge. In the primary cell, oxidation and reduction reactions occur at two electrodes: oxidation occurs at the negative electrode, and reduction occurs at the positive electrode. Electrons flow from the negative electrode to the positive electrode through the external circuit. Connecting the two electrodes to a voltmeter can measure the terminal voltage of the primary cell at this time, which can roughly determine the electromotive force E of the primary cell, E = Φ + - Φ - . Taking a copper-zinc primary cell as an example, this experiment mainly uses Cu sheet, Zn sheet, CuSO4(1 mol*L -1 ), ZnSO4(1 mol*L -1 ), KCl salt bridge, etc. to form a primary cell. The zinc electrode serves as the negative electrode and undergoes oxidation, with the electrode reaction formula: Zn - 2e - = Zn 2+ ; the copper electrode serves as the positive electrode and undergoes reduction, with the electrode reaction formula: Cu 2+ + 2e - = Cu; the total reaction equation of the cell is Zn + Cu 2+ = Zn 2+ + Cu.

[0003] The determination of the electromotive force of the primary cell has important practical significance in the study of physical chemistry experiments. Determining the electromotive force of the primary cell helps to deepen the understanding of basic concepts of electrochemistry, deepen the understanding of the composition and working principle of electrochemical systems, and obtain many thermodynamic functions of chemical systems, which provides an important basis for studying the direction and limit of chemical reactions, studying chemical reaction kinetics, and guiding the research and optimization of chemical power sources. However, current reports on the determination of the electromotive force of the primary cell mainly focus on the design and improvement of electrolytic cells, such as using a glass container with a round hole as an electrolytic cell, connecting the electrode, salt bridge, voltmeter and wire together to form a primary cell, and then measuring the electromotive force of the primary cell through the voltmeter.

[0004] Chinese utility model patent CN211402662U discloses a kind of experimental device of battery electromotive force determination, the glass tank with electrolyte is arranged below electrode stick, and cover plate is provided on the upper end of glass tank, the round hole for glass tube to pass through and enter glass tank is provided on the cover plate.Then the electromotive force of primary cell is determined by voltmeter.Chinese utility model patent CN219978184U discloses a kind of device for measuring the electrochemical performance of electrolyte solution at constant temperature, which can determine the electromotive force of non-metallic oxidation-reduction reaction under constant temperature condition by designing a constant temperature jacket to simulate a constant temperature environment.

[0005] Although the above reports have designed and developed the structure of electrolytic cell to some extent, the existing determination device still has the following problems in the experimental process: (1) the electrode sheet is easy to shake, the electrolyte is easy to spill, and the salt bridge is easy to tilt in the process of shaking or shaking the electrolytic cell, which leads to experimental failure; (2) it is inconvenient to add electrolyte to the electrolytic cell; (3) the glass electrolytic cell without protection is easy to break during operation, which may cause safety accidents; (4) the device is complex in design and tedious in operation. Content of the utility model

[0006] To solve the above problems, the utility model aims to provide a primary cell electromotive force testing device for ordinary chemical experiments, which can shield the influence of external disturbance on the stability of the device to some extent, and the reaction container, salt bridge and electrode sheet can be detached, so that the electrode sheet, salt bridge, reaction container and electrolyte can be replaced in time, the structure is simple, the operation is convenient, and the operation safety, experimental efficiency and test result accuracy of the experimental device can be improved.

[0007] To achieve the above purpose, the utility model adopts the following technical solutions:

[0008] A primary cell electromotive force determination device for ordinary chemical experiments includes a voltmeter, a metal inner shell cover, a metal outer shell cover, a metal outer shell, a metal inner shell, a first reaction container, a second reaction container, a positive electrode sheet, a salt bridge, a negative electrode sheet, an electrode plate and a screw.

[0009] The metal outer shell cover is detachably arranged on the metal outer shell; the metal inner shell cover is detachably arranged on the metal inner shell, and the metal inner shell cover and the metal inner shell are arranged in the metal outer shell; the voltmeter is fixedly connected to the longitudinal panel on the upper part of the metal outer shell; the first reaction container and the second reaction container are arranged in the metal inner shell respectively; the metal inner shell cover is provided with protrusions for fixing the first reaction container and the second reaction container respectively; the protrusions are composed of two parts, which are a frame-shaped protrusion matched with the inner side dimension of the metal inner shell and a protrusion matched with the outer radial dimension of the first reaction container and the second reaction container; the first reaction container and the second reaction container contain the corresponding positive electrolyte solution and negative electrolyte solution respectively as needed;

[0010] The metal inner shell cover is provided with a salt bridge hole through which the salt bridge is inserted into the positive electrolyte solution and the negative electrolyte solution respectively; the inner wall of the first reaction container and the second reaction container is respectively provided with a clamping groove in a radial symmetry, the clamping groove is a groove structure and is integrally formed with the reaction container, the length of the clamping groove along the y-axis direction is adapted to the thickness of the electrode plate so that the electrode plate can move up and down along the clamping groove; the electrode plate is fixed in the reaction container through the clamping groove and can move up and down along the clamping groove.

[0011] The positive electrode plate and the negative electrode plate are respectively detachably fixed on the electrode plate through screws; the metal inner shell cover is further provided with a wiring hole through which a lead wire connects the electrode plate with a voltmeter.

[0012] Further, the metal outer shell and the metal inner shell are made of stainless steel.

[0013] Further, the longitudinal length of the clamping groove is 0.80-1.00 cm.

[0014] Further, the first reaction container and the second reaction container are both integrally formed with the clamping groove.

[0015] Further, the salt bridge hole is a circular hole with a diameter of 0.80-1.20 cm.

[0016] Further, the wiring hole is a circular hole, a square hole or a rhombic hole.

[0017] Further, the positive electrode plate and the negative electrode plate can be selected according to experimental requirements, the positive electrode plate can be a Cu plate, and the negative electrode plate can be a Zn plate; the positive electrolyte solution and the negative electrolyte solution can be CuSO4 solution and ZnSO4 solution respectively.

[0018] Compared with the prior art, the ordinary chemical experiment primary cell electromotive force measuring device has the following beneficial effects:

[0019] 1. The ordinary chemical experiment primary cell electromotive force measuring device can fix the reaction container and the salt bridge through the metal inner shell cover, fix the electrode plate, the positive electrode plate and the negative electrode plate through the reaction container with the clamping groove, and shield the influence of external disturbance on the stability of the device to a certain extent.

[0020] 2. The reaction container, the salt bridge and the electrode plate in the ordinary chemical experiment primary cell electromotive force measuring device are detachable, the electrode plate, the salt bridge, the reaction container and the electrolyte solution can be replaced in time, the structure is simple, and the operation is convenient.

[0021] 3. The primary cell electromotive force measuring device for ordinary chemical experiments has the metal shell and the inner shell, so that the primary cell is protected, and the operation safety of the experimental device is further improved.

[0022] 4. The primary cell electromotive force measuring device for ordinary chemical experiments has the voltmeter designed on the metal shell, so that the experimental efficiency is improved, and the measurement of the primary cell electromotive force is convenient and fast.

[0023] 5. The experimental results show that the relative error of the measurement result is less than 2% by using the device to measure the primary cell electromotive force, and the test result accuracy is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a structural schematic view of the primary cell electromotive force measuring device for ordinary chemical experiments provided by the embodiment of the utility model;

[0025] Figure 2 is a primary cell main part schematic view of the primary cell electromotive force measuring device for ordinary chemical experiments provided by the embodiment of the utility model;

[0026] Figure 3 is a metal inner shell cover schematic view of the primary cell electromotive force measuring device for ordinary chemical experiments provided by the embodiment of the utility model;

[0027] Figure 4 is a reaction container schematic view of the primary cell electromotive force measuring device for ordinary chemical experiments provided by the embodiment of the utility model.

[0028] In the drawing: 1. voltmeter; 2. metal inner shell cover; 3. metal shell cover; 4. metal shell; 5. metal inner shell; 6. first reaction container; 7. positive electrode electrolyte solution; 8. positive electrode sheet; 9. salt bridge; 10. negative electrode electrolyte solution; 11. negative electrode sheet; 12. electrode plate; 13. clamping groove; 14. screw; 15. wiring hole; 16. salt bridge hole; 17. second reaction container. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the utility model more clear, the utility model will be described in more detail in combination with the drawings and specific embodiments of the specification, but the utility model is not limited to this.

[0030] In the description of the utility model, it needs to explain, the terms "upper", "lower", "center", "front", "back", "left", "right", "inner", "outer" and so on indicate the orientation or position relation based on the orientation or position relation shown in the drawing, just for the convenience of describing the utility model and simplifying the description, and not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the utility model.

[0031] Figure 1 A common chemical experiment is shown in the figure after assembling a primary cell electromotive force measuring device, which comprises: voltmeter 1, metal inner shell cover 2, metal outer shell cover 3, metal shell 4, metal inner shell 5, first reaction container 6, positive electrolyte solution 7, positive electrode plate 8, salt bridge 9, negative electrolyte solution 10, negative electrode plate 11, electrode plate 12, clamping groove 13, screw 14, second reaction container 17.

[0032] The metal outer shell cover 3 is detachably arranged on the metal shell 4; the metal inner shell cover 2 is detachably arranged on the metal inner shell 5, and the metal inner shell cover 2 and the metal inner shell 5 are arranged in the metal shell 4; the voltmeter 1 is fixedly connected to the longitudinal panel on the upper part of the metal shell 4; the first reaction container 6 and the second reaction container 17 are arranged in the metal inner shell 5 respectively; the metal inner shell cover 2 is provided with protrusions for fixing the first reaction container 6 and the second reaction container 17 respectively, the protrusions are composed of two parts, which are a frame-shaped protrusion matched with the inner side dimension of the metal inner shell 5 and a protrusion matched with the outer radial dimension of the two reaction containers, the frame-shaped protrusion fixes the metal inner shell cover 2 on the metal inner shell 5 through the characteristics matched with the inner side dimension of the metal inner shell 5, and the protrusion matched with the outer radial dimension of the two reaction containers fixes the first reaction container 6 and the second reaction container 17 in the metal inner shell through the characteristics matched with the outer radial dimension of the two reaction containers. The first reaction container 6 and the second reaction container 17 contain the positive electrolyte solution 7 and the negative electrolyte solution 10 respectively; wherein the metal outer shell cover 3 can be removed during use; the metal inner shell cover 2 can be freely disassembled during assembly and disassembly of the primary cell; the longitudinal panel is a longitudinal panel structure on the upper part of the metal shell 4. Preferably, the metal shell and the metal inner shell are made of stainless steel.

[0033] The metal inner shell cover 2 is provided with salt bridge holes 16, through which salt bridges 9 are inserted into the positive electrode electrolyte solution 7 and the negative electrode electrolyte solution 10 respectively. The inner walls of the first reaction vessel 6 and the second reaction vessel 17 are respectively provided with radially symmetrical slots 13. The slots 13 are groove-type structures, integrally formed with the reaction vessels. The length of the slots 13 along the y-axis is adapted to the thickness of the electrode plates, allowing the electrode plates to move up and down along the slots. The electrode plates 12 are fixed inside the reaction vessels through the slots 13 and can move up and down along the slots 13. Preferably, the longitudinal length of the slots 13 is 0.80-1.00 cm. The salt bridge holes 16 are preferably circular holes with a diameter of 0.80-1.20 cm.

[0034] The positive electrode 8 and the negative electrode 11 are detachably fixed to the electrode plate 12 by screws; the metal inner shell cover 2 is also provided with a wiring hole 15, through which the wire passes to connect the electrode plate 12 to the voltmeter 1. The wiring hole 15 is preferably a round hole, a square hole or a diamond-shaped hole.

[0035] like Figure 2 As shown, the first reaction vessel 6 and the second reaction vessel 17 are fixed inside the metal inner shell 5 by the metal inner shell cover 2. Preferably, both the first reaction vessel 6 and the second reaction vessel 17 are integrally formed beakers with slots.

[0036] like Figure 3 As shown, the metal inner shell cover 2 is provided with symmetrically arranged salt bridge holes 16 and wiring holes 15, as well as protrusions for fixing the inner shell cover 2 and the two reaction vessels 6 and 17. The salt bridge holes 16 and wiring holes 15 on both sides are symmetrically located inside the two circular frame-shaped protrusions. The protrusions on the metal inner shell cover 2 for fixing the reaction vessels are fixed to the metal inner shell cover 5 by the frame-shaped protrusions that are adapted to the inner dimensions of the metal inner shell 5. The first reaction vessel 6 and the second reaction vessel 17 are fixed inside the metal inner shell 5 by the two circular frame-shaped protrusions that are adapted to the outer radial dimensions of the two reaction vessels.

[0037] like Figure 4 As shown, the electrode plate 12 is fixed inside the reaction vessel by the slot 13 on the reaction vessel, and the positive electrode 8 and the negative electrode 11 are fixed on the electrode plate 12 by screws 14 respectively; the assembly and disassembly of the positive electrode 8 and the negative electrode 11 can be controlled by the screws 14.

[0038] The positive electrode 8, positive electrolyte solution 7, salt bridge 9, negative electrolyte solution 10, negative electrode 11, and voltmeter 1 form a circuit through wires. The terminal voltage can be read from the voltmeter to obtain the electromotive force of the galvanic cell. Taking a copper-zinc galvanic cell as an example, the positive electrode is a Cu sheet, and the negative electrode is a Zn sheet; the corresponding electrolyte solutions are CuSO4 solution and ZnSO4 solution, respectively.

[0039] When preparing the experiment, the metal inner shell cover can be opened to take out the reaction container, and the corresponding electrolyte solution is added outside the device, and the electrode plate, the positive electrode plate and the negative electrode plate are assembled.

[0040] The positive electrode plate, the positive electrolyte solution, the salt bridge, the negative electrolyte solution, the negative electrode plate and the voltmeter are connected by wires, at this time, the terminal voltage can be read by the voltmeter, and the electromotive force of the primary cell is obtained.

[0041] The use process of the primary cell electromotive force measuring device for general chemical experiments is:

[0042] According to Figure 1 The primary cell electromotive force measuring device is installed.

[0043] Taking a copper-zinc primary cell as an example, the sandpaper-polished Zn sheet is inserted into the ZnSO4 solution (1 mol*L -1 ) through the electrode plate fixed on the card slot, the Cu sheet is inserted into the CuSO4 solution (1 mol*L -1 ) through the electrode plate fixed on the card slot, and the CuSO4 solution and the ZnSO4 solution are connected by the KCl salt bridge. The Zn sheet and the Cu sheet are connected to the voltmeter through the voltmeter side terminal post by wires, and the primary cell is formed.

[0044] The terminal voltage of the primary cell is measured and recorded, and the approximate electromotive force of the primary cell is obtained. The device is tested in parallel for six times, and the results are shown in Table 1.

[0045] Table 1: Primary cell electromotive force measurement results

[0046]

[0047] As shown in Table 1, the relative error obtained by six experimental results is below 2%, which indicates that the measurement result of the primary cell electromotive force measuring device for general chemical experiments is accurate and high.

[0048] The utility model discloses a primary cell electromotive force measuring device outside adopts stainless steel material metal shell, and the shell surface is equipped with voltmeter. The device is equipped with inner shell, and the inner shell cover of inner shell can be dismantled, and the inner shell cover is equipped with the protrusion of fixed reaction container, the salt bridge hole of fixed salt bridge and the wiring hole of allowing wire to pass, and the inner shell is equipped with the reaction container of removable slot, and the reaction container is equipped with the electrolyte solution of corresponding respectively according to actual experiment demand, and the electrode plate can move up and down along the slot on the reaction container and complete dismounting, and can be fixed by the slot simultaneously, the positive pole piece, negative pole piece are fixed with electrode plate through screw to insert into electrolyte solution, and the salt bridge can insert into electrolyte solution through the salt bridge hole on the inner shell cover, and the wire can be connected with voltmeter and electrode plate through the wire insertion hole on the inner shell cover. The utility model discloses a reaction container of slot, and the electrode plate can be fixed by inserting into the slot, and the electrode plate can also move up and down along the slot and complete dismounting, and the pole piece can be fixed on the electrode plate by screw when measuring electromotive force, guaranteeing the stability and accuracy of data when electromotive force test, and the inner shell cover on the inner shell can be opened, and the electrolyte solution in the reaction container can be added and the pole piece can be installed directly outside the device after taking out the reaction container, facilitating the assembly of primary cell and improving the experimental efficiency, and the setting of metal shell reduces the contact degree of electrolyte solution and air, effectively avoiding the problem of falling impurity dust in the reaction container, and the voltmeter, pole piece, electrolyte solution and salt bridge are integrated, improving the operation safety and experimental efficiency. The electromotive force of primary cell is measured by the utility model device, and the relative error is below 2%.

[0049] It should be noted that the above-described embodiments are only preferred embodiments of the utility model. For ordinary skilled in the art, without departing from the principles of the utility model, the utility model can be modified, improved and equivalent replaced, and these modifications, improvements and equivalent replacements are also considered to fall within the protection scope of the utility model claims.

Claims

1. A device for measuring the electromotive force of a galvanic cell used in common chemical experiments, characterized in that, The voltmeter, the metal inner shell cover, the metal outer shell cover, the metal outer shell, the metal inner shell, the first reaction container, the second reaction container, the positive electrode sheet, the salt bridge, the negative electrode sheet, the electrode plate, and the screw are included. The metal outer shell cover is detachably arranged on the metal outer shell, and the metal inner shell cover is detachably arranged on the metal inner shell, wherein the metal inner shell cover and the metal inner shell are arranged in the metal outer shell; the voltmeter is fixedly connected to the longitudinal panel on the upper portion of the metal outer shell; the first reaction container and the second reaction container are arranged in the metal inner shell, respectively; the metal inner shell cover is provided with protrusions for fixing the first reaction container and the second reaction container, respectively, wherein the protrusions are composed of two parts, namely, a frame-shaped protrusion matched with the inner side dimension of the metal inner shell and a protrusion matched with the outer radial dimension of the first reaction container and the second reaction container; the first reaction container and the second reaction container contain the positive electrolyte solution and the negative electrolyte solution, respectively, as needed. The metal inner shell cover is provided with a salt bridge hole, and the salt bridge is inserted into the positive electrolyte solution and the negative electrolyte solution, respectively, through the salt bridge hole; the inner walls of the first reaction container and the second reaction container are respectively provided with card slots in radial symmetry, wherein the card slots are groove-shaped structures and are integrally formed with the reaction containers, the length of the card slots in the y-axis direction is matched with the thickness of the electrode plate to enable the electrode plate to move up and down along the card slots; the electrode plate is fixed in the reaction container through the card slots and can move up and down along the card slots. The positive electrode sheet and the negative electrode sheet are detachably fixed on the electrode plate through the screw, respectively; the metal inner shell cover is further provided with a wiring hole, and a wire passes through the wiring hole to connect the electrode plate with the voltmeter.

2. The device for measuring the electromotive force of a galvanic cell for general chemistry experiments according to claim 1, characterized by The metal outer shell and the metal inner shell are made of stainless steel.

3. The device for measuring the electromotive force of a galvanic cell for general chemistry experiments according to claim 1, characterized by The longitudinal length of the card slot is 0.80-1.00 cm.

4. The device for measuring the electromotive force of a galvanic cell for general chemistry experiments according to claim 1, characterized by Both the first reaction container and the second reaction container are integrally formed with card slots.

5. The device for measuring the electromotive force of a galvanic cell for general chemistry experiments according to claim 1, characterized by The salt bridge hole is a circular hole with a diameter of 0.80-1.20 cm.

6. The device for measuring the electromotive force of a galvanic cell for general chemistry experiments according to claim 1, characterized by The wiring hole is a circular hole, a square hole, or a rhombic hole.

7. The device for measuring the electromotive force of a galvanic cell for general chemistry experiments according to claim 1, characterized by The positive electrode sheet can be a Cu sheet, and the negative electrode sheet can be a Zn sheet; the positive electrolyte solution and the negative electrolyte solution can be CuSO4 solution and ZnSO4 solution, respectively.

Images