Injection type experimental method for accurately measuring specific heat capacity of metal

Abstract

The invention discloses an injection type experimental method for accurately measuring the specific heat capacity of metal, which comprises the following steps: selecting a calorimeter body, arranging an injection mechanism for injecting liquid into the calorimeter body on a barrel cover (4) of the calorimeter body, namely, processing a cylindrical hole (41) on the barrel cover (4), and covering the cylindrical hole (41) with a rubber plug (8); the upper end face of the rubber plug (8) is connected with the rubber plug seat (82) through a connecting piece (81), and the rubber plug (8) can automatically stand above the rubber plug seat (82) when opened. In the process of adding high-temperature water or low-temperature water into a system, a barrel cover (4) of the calorimeter does not need to be opened, the high-temperature water or the low-temperature water is directly injected into the calorimeter through a cylindrical hole (41) by adopting a water injection barrel (11), only the small cylindrical hole (41) is communicated with the outside, and meanwhile, due to the fact that a rubber plug (8) is rapidly opened and closed, the calorimeter is convenient to use. The heat dissipation area and the heat dissipation time of the high-temperature liquid to the environment are greatly reduced, and the measurement precision of the metal specific heat capacity is remarkably improved.

Description

Technical Field

[0001] The invention relates to a physical experiment teaching instrument, in particular to an injection-type experimental method for accurately measuring the specific heat capacity of metals. Background Art

[0002] Calorimeter is a commonly used teaching experiment instrument in college physics teaching. It is used to measure the temperature change inside an isolated system without heat exchange with the outside world. The calorimeter can be used to measure the melting heat of ice, the specific heat capacity of non-metallic materials, etc. using the mixed calorimetry method. However, it will produce large errors when measuring the specific heat capacity of metal materials.

[0003] The mixing method is used to measure the specific heat capacity of metals in a calorimeter. The basic principle is that a system I with an initial temperature of T1 is mixed with a system II with a temperature of T2. The equilibrium temperature after mixing is T3. If the heat exchange with the outside world is not considered, the heat absorbed by the low-temperature system II is equal to the heat released by the high-temperature system I. The heat balance equation is:

[0004] C I (T1-T3) = C II (T3-T2) <1>

[0005] C I , C II is the heat capacity of system I and system II.

[0006] In actual measurement, a metal block to be measured is mixed with water to complete the measurement. Since the temperature of the metal block is not convenient to measure, and the room temperature is a stable temperature, the metal block is generally set to room temperature (set as low temperature system II), and the temperature in the calorimeter (set as high temperature system I including water, agitator and temperature measuring device, etc.) needs to be measured before the metal block is put in to mix the two. Since the characteristics of metal materials are fast thermal conductivity and small heat capacity, it is easy for the temperature of the system in the calorimeter after equilibrium to be not much different from the previous water temperature, which brings a large relative error to the experimental results. Therefore, it is generally required that the temperature of the water in the calorimeter should be as large as possible from the temperature of the metal block, that is, the temperature difference between the initial temperature of system I and system II should be larger, and high temperature water of about 70°C is generally used to meet the experimental requirements.

[0007] There are many ways to mix System I and System II, but no matter which one you choose, you need to first measure the initial temperatures T1 and T2 of System I and System II, and then mix them. However, during the mixing process, it takes a long time to open the lid of the calorimeter, and the high-temperature substances in System I or System II will lose heat to the environment, which will change the initial temperature and cause a large error in the measurement result. Take the example of putting a metal block into the calorimeter, there are the following two situations:

[0008] (1) If the solution adopted is: the interior of the calorimeter contains high-temperature water, after the initial temperature is measured, it is necessary to open the lid of the calorimeter and put in a metal block, and then close the lid of the calorimeter to measure the temperature after equilibrium. Because the cylinder cover 4 is also equipped with a stirrer 5 and a thermometer and other components, some calorimeter cylinder covers need to be more accurately aligned with the inner and outer cylinders of the calorimeter before they can be closed tightly. In addition, it takes a long time to clamp the metal block and put it in, so this process takes a long time to complete. During the period when the calorimeter cover is opened, a large amount of heat in the high temperature of the calorimeter system is dissipated in the space, causing a large change in the initial temperature of the system, resulting in inaccurate measurement results.

[0009] (2) If the solution adopted is: the inside of the calorimeter is low-temperature water, it is necessary to open the lid of the calorimeter, put in a high-temperature metal block, and then cover the lid to measure the temperature after equilibrium. The problems are: first, the initial temperature of the metal block is difficult to measure. Generally, the temperature of the high-temperature water measured after heating it in high-temperature water represents the initial temperature of the metal block. However, it takes time to transfer the high-temperature metal block. First, the high-temperature metal block dissipates heat very quickly (the metal block is a material of instantaneous equilibrium). After being taken out of the high-temperature water, it cools down rapidly. After being put into the calorimeter, its initial temperature has changed significantly. Second, the metal block carries a lot of high-temperature water, which also has a great influence on the experimental results. Experiments have shown that this experimental solution produces the largest error.

[0010] Practice has shown that after the metal block is put into the calorimeter, it reaches thermal equilibrium in a very short moment to complete the experiment. If the operation is correct, the heat exchange between the calorimeter and the environment in other links is very small, even negligible. Therefore, in order to make the experiment successful, first, the time when the calorimeter cover is fully opened should be shortened as much as possible to minimize the time when the high-temperature system loses heat to the environment. Second, when mixed calorimetry is performed, the heat dissipation area of ​​the calorimeter system when it is open should be minimized. However, the existing experimental methods can no longer meet such requirements. Summary of the invention

[0011] The purpose of the present invention is to overcome the shortcomings of the calorimeter in the background technology, improve the existing technology, and provide an experimental method for accurately measuring the specific heat capacity of metals without opening the calorimeter tube cover 4 and quickly completing the injection of high-temperature or low-temperature water into the calorimeter, greatly reducing the heat loss of the high-temperature system to the environment.

[0012] The objective of the present invention is achieved through the following technical solutions:

[0013] An injection-type experimental method for accurately measuring the specific heat capacity of metals Figure 1 As shown;

[0014] Select a calorimeter body, and set an injection mechanism on the cylinder cover 4 of the calorimeter body for injecting liquid into the calorimeter body;

[0015] The calorimeter body includes an inner cylinder 1 and an outer cylinder 2, both of which are metal cylinders with closed bottoms. The upper edges of the inner cylinder 1 and the outer cylinder 2 are formed into arc shapes outward. The inner cylinder 1 is placed at the bottom of the outer cylinder 2 through an insulating pad 3, and a uniform gap is left between the inner cylinder 1 and the outer cylinder 2.

[0016] The cylinder cover 4 is a stepped cylinder made of engineering plastics. The upper part of the cylinder cover 4 is a cylinder with a larger diameter, and the lower end surface of the stepped part is buckled on the upper edge of the outer cylinder 2. The lower part is a cylinder with a smaller diameter, and the lower end surface of the small cylinder covers the upper edge of the inner cylinder 1. The cylinder cover 4 is provided with a stirrer hole 10, and an injection mechanism for injecting liquid into the inner cylinder 1 of the calorimeter body is provided on the cylinder cover 4 opposite to the stirrer hole 10.

[0017] The injection mechanism is a cylindrical hole 41 processed on the cylinder cover 4, and the cylindrical hole 41 must be within the range of the cylinder cover 4 corresponding to the inner cylinder 1, and a square groove 42 is processed on the side of the cylindrical hole 41;

[0018] The cylindrical hole 41 connects the space of the inner cylinder 1 of the calorimeter body with the space outside the cylinder cover 4;

[0019] The cylindrical hole 41 has a diameter of 10-15 mm and is covered with a rubber plug 8, which isolates the space of the inner cylinder 1 of the calorimeter body from the space outside the cylinder cover 4;

[0020] The rubber plug 8 is in the shape of a truncated cone, the upper end surface of which is connected to the rubber plug seat 82 via a connecting piece 81. The rubber plug seat 82 is embedded in the square groove 42 on the cylinder cover 4 and is fixedly bonded to the square groove 42. The connecting piece 81 is higher than the upper plane of the cylinder cover 4. When the rubber plug 8 is opened, it automatically stands above the rubber plug seat 82 under the elastic force of the connecting piece 81 and does not block the cylindrical hole 41.

[0021] The injection mechanism further comprises a water injection cylinder 11; the water injection cylinder 11 is a cylindrical water cylinder with a capacity of 300 ml, with a scale 13 on the cylinder body, a nozzle 14 at the bottom of the cylinder body, a film 15 on the nozzle 14, and a handle 16 on the upper side of the cylinder body;

[0022] The water injection cylinder 11 is made of a plastic material that can withstand relatively high temperatures, and the film 15 is made of a rubber material that has good elasticity and can withstand relatively high temperatures.

[0023] The rubber plug 8, the connecting piece 81 and the rubber plug seat 82 are all made of a rubber material with good elasticity.

[0024] The experimental method for accurately measuring the specific heat capacity of metal by injection also requires the metal 9 to be measured.

[0025] The experimental method using the above experimental device is:

[0026] 1. The inside of the calorimeter is high temperature water plus the metal to be tested 9 as the high temperature system I

[0027] (1) First mass measurement: Before the experiment, measure the masses of the inner cylinder 1, the stirrer 5, the inner cylinder 1 + high-temperature water, and the metal to be tested 9 respectively;

[0028] (2) Add high-temperature water and the metal to be tested 9 into the calorimeter, stir gently with a stirrer 5, and measure the initial temperature T1 of the high-temperature system after equilibrium. The value of T1 should be about 70°C;

[0029] (3) After the initial temperature is measured, low-temperature water needs to be added to the calorimeter, that is, the initial temperature of the low-temperature system II is T2. The method is to open the rubber plug 8, inject an appropriate amount of room temperature water into the inner tube 1 through the cylindrical hole 41 using the water injection cylinder 11, and then quickly press the rubber plug 8 to close the system, and read the final temperature T3 of the system after equilibrium on the display 6;

[0030] The method of injecting room temperature water into the inner cylinder 1 with the water injection cylinder 11 is as follows: cover and tightly cover the nozzle 14 with the film 15, add a proper amount of room temperature water into the water injection cylinder 11, and monitor the water temperature with a thermometer, then insert the nozzle 14 into the cylindrical hole 41, pierce the film 15 with a long bamboo stick 17, and inject the room temperature water in the water injection cylinder 11 into the inner cylinder 1;

[0031] (4) Second mass measurement: After the experimental operation is completed, measure the mass of the inner cylinder 1 + agitator 5 + metal to be tested 9 + high-temperature water + low-temperature water. The mass of the low-temperature water can be obtained after calculation;

[0032] (5) Calculate the heat capacity C of the mass of the relevant substance I , C II , where C I The specific heat capacity of the unknown metal 9 to be measured is included;

[0033] (6) Substitute all known quantities into the heat balance equation <1> , the specific heat capacity of the metal 9 to be tested can be calculated;

[0034] 2. The inside of the calorimeter is the low temperature metal to be tested 9 or the low temperature metal to be tested 9 plus low temperature water as the low temperature system II

[0035] (1) First mass measurement: Before the experiment, measure the masses of the inner cylinder 1, the stirrer 5, the inner cylinder 1 + low-temperature water, and the metal to be tested 9 respectively;

[0036] (2) If there is only the metal to be tested 9 in the inner cylinder 1, it can be directly set to room temperature, that is, the initial temperature T2 of the system II; if the metal to be tested 9 with low temperature is added with water in the inner cylinder 1, the initial equilibrium temperature T2 of the system can be measured by the sensor 7 and the display 6;

[0037] (3) Use the water injection cylinder 11 to inject an appropriate amount of high-temperature water with a temperature of T1 into the inner cylinder 1 through the cylindrical hole 41, then quickly press the rubber plug 8 to close the system, and read the final temperature T3 of the system after equilibrium on the display 6;

[0038] The method of injecting high-temperature water into the inner cylinder 1 with the water injection cylinder 11 is as follows: the nozzle 14 is covered and tightly covered with a film 15, the water injection cylinder 11 is placed in a container filled with high-temperature water, and a proper amount of high-temperature water is added into the water injection cylinder 11, and the water temperature is monitored with a thermometer to maintain the temperature at T1. When water needs to be injected into the inner cylinder 1, the nozzle 14 is inserted into the cylindrical hole 41, and the film 15 is pierced with a long bamboo stick 17. After the film 15 is broken, it quickly shrinks on the edge of the nozzle 14, and the high-temperature water in the water injection cylinder 11 is quickly injected into the inner cylinder 1;

[0039] (4) Second mass measurement: After the experiment is completed, the mass of the inner cylinder 1 + the stirrer 5 + the metal to be tested 9 + water (including high-temperature water and low-temperature water) is measured. The mass of the high-temperature water can be obtained by calculation. If there is only the metal to be tested 9 but no low-temperature water in the inner cylinder 1 before mixing, the mass of the water measured after the experiment is completed is all the mass of the high-temperature water.

[0040] (5) Calculate the heat capacity C of the mass of the relevant substance I , C II , where C II The specific heat capacity of the unknown metal 9 to be measured is included;

[0041] (6) Substitute all known quantities into the heat balance equation <1> , the specific heat capacity of the metal 9 to be tested can be calculated;

[0042] It can be seen from the technical solution provided by the present invention that the beneficial effect of the experimental method for accurately measuring the specific heat capacity of metals by injection provided by the present invention is that it overcomes the difficulties in the background technology: (1) When it is necessary to add high-temperature water or low-temperature water to the inside of the calorimeter body, it is only necessary to open the rubber plug 8 of the injection mechanism, and use the water injection cylinder 11 filled with water of a certain temperature and a certain amount to inject it into the inner cylinder 1 of the calorimeter body through the cylindrical hole 41. There is no need to open the cylinder cover 4 of the calorimeter. Only the cylindrical hole 41 connects the inner cylinder 1 with the external environment, thereby avoiding the high-temperature water in the inner cylinder 1 or the high-temperature water in the water injection cylinder 11 from contacting with the environment in a large range during the injection process into the inner cylinder 1, resulting in a large heat loss. It also avoids the need to completely open the calorimeter cylinder cover 4 and then pour in high-temperature water in the traditional experimental method, which causes the flowing and tumbling high-temperature water to quickly dissipate heat to the environment; (2) Open the rubber plug 8 by hand, and under the elastic force of the connecting piece 81, the rubber plug 8 automatically stands on the top of the rubber plug seat 82, without blocking the cylindrical hole 41, making it convenient for the water injection cylinder to inject liquid into the inner cylinder 1. After the operation is completed, the rubber plug 8 can be directly pressed by hand to plug the cylindrical hole 41, and the operation of filling the calorimeter with liquid can be completed in a very short time, greatly reducing the time of opening the calorimeter system. Therefore, this experimental method greatly reduces the heat dissipation area to the environment during the system mixing process, and greatly reduces the time for the calorimeter system to generate heat exchange with the outside world, greatly improving the accuracy of the measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0044] Figure 1 A schematic diagram of the structure of a device required for an experimental method for accurately measuring the specific heat capacity of metals by injection provided in an embodiment of the present invention.

[0045] Figure 2 A schematic diagram of injecting liquid in an experimental method for accurately measuring the specific heat capacity of metals by injection provided in an embodiment of the present invention.

[0046] Figure 3 The present invention is a top view of a cylinder cover used in an experimental method for accurately measuring the specific heat capacity of metals by injection.

[0047] Figure 4 This is a schematic diagram of an experimental method for accurately measuring the specific heat capacity of metals by injection according to the present invention, with the cylinder cover closing the rubber plug.

[0048] Figure 5The AA cross-sectional view of the injection mechanism of the experimental method for accurately measuring the specific heat capacity of metals by injection according to the present invention.

[0049] Figure 6 The present invention is a schematic diagram of the structure of a water injection cylinder for an experimental method for accurately measuring the specific heat capacity of metals by injection.

[0050] In the figure: 1, inner cylinder, 2, outer cylinder, 3, insulation pad, 4, cylinder cover, 41, cylindrical hole, 42, square groove, 5, stirrer, 6, display, 7, sensor, 8, rubber plug, 81, connecting piece, 82, rubber plug seat, 9, metal to be tested, 10, stirrer hole, 11, water injection cylinder, 12, temperature measuring hole, 13, scale, 14, nozzle, 15, film, 16, handle 17, long bamboo stick. DETAILED DESCRIPTION

[0051] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0052] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0053] The present invention provides an injection-type experimental method for accurately measuring the specific heat capacity of metals, and its preferred specific implementation is shown in the accompanying drawings.

[0054] An experimental method for accurately measuring the specific heat capacity of metal by injection is provided. A calorimeter body is selected, and a cylinder cover 4 is provided on the upper end of the calorimeter body.

[0055] In a conventional calorimeter, the calorimeter body generally comprises an inner cylinder 1 and an outer cylinder 2. The inner cylinder 1 is placed inside the outer cylinder 2 via an insulating pad 3. The cylinder cover 4 is a stepped cylinder made of engineering plastic. The upper portion of the cylinder cover 4 is a cylinder with a larger diameter, and the lower end surface of the stepped portion is buckled on the upper edge of the outer cylinder 2. The lower portion is a cylinder with a smaller diameter, and the lower end surface of the small cylinder covers the upper edge of the inner cylinder 1. The cylinder cover 4 is provided with a stirrer hole 10 and a temperature measuring hole 12 for measuring temperature.

[0056] In order to avoid opening the cylinder cover 4 completely during the experiment, in the present application, an injection mechanism for injecting liquid into the interior of the calorimeter body is specially provided on the cylinder cover 4 of the calorimeter.

[0057] The injection mechanism is arranged on the cylinder cover 4 on the other side opposite to the stirrer hole 10, that is, a cylindrical hole 41 is processed on the cylinder cover 4, and the cylindrical hole 41 must also be within the range of the cylinder cover 4 corresponding to the inner cylinder 1. A square groove 42 is processed on the side of the cylindrical hole 41, and the cylindrical hole 41 connects the space of the inner cylinder 1 of the calorimeter body with the space outside the cylinder cover 4;

[0058] The cylindrical hole 41 is covered with a rubber plug 8, which isolates the space inside the cylinder 1 of the calorimeter body from the space outside the cylinder cover 4;

[0059] In order to facilitate the rapid opening and closing of the plug 8, the plug 8, the connecting piece 81 and the plug seat 82 are all made of a rubber material with good elasticity. The plug 8 is in the shape of a truncated cone, and the upper end surface of the truncated cone is connected to the plug seat 82 through the connecting piece 81. The plug seat 82 is embedded in the square groove 42 on the cylinder cover 4 and fixedly bonded to the square groove 42. The connecting piece 81 is higher than the upper plane of the cylinder cover 4. It is required that when the plug 8 is opened, it is automatically erected above the plug seat 82 under the action of the elastic force of the connecting piece 81 without blocking the cylindrical hole 41.

[0060] The injection mechanism also includes a water injection cylinder 11; the water injection cylinder 11 is a cylindrical water cylinder with a capacity of 300 ml, with a scale 13 on the cylinder body, a nozzle 14 at the bottom of the cylinder body, a film 15 on the nozzle 14, a handle 16 on the upper side of the cylinder body, and a long bamboo stick 17;

[0061] The water injection tube 11 needs to contact high temperature water, so the water injection tube 11 is made of plastic material that can withstand high temperature, and the film 15 is made of rubber film that can withstand high temperature and has good elasticity. But in fact, the temperature of high temperature water is generally kept at about 70°C.

[0062] An experimental method for accurately measuring the specific heat capacity of metals by injection, which also requires the metal to be measured 9.

[0063] The rubber plug 8, the connecting piece 81 and the rubber plug seat 82 are all made of a rubber material with good elasticity.

[0064] The cylindrical hole 41 should not be too large, and a diameter of 10-15 mm is preferred.

[0065] This experimental device is not suitable for measuring temperature with an ordinary thermometer, as the metal 9 to be measured is likely to break the temperature measuring bulb of an ordinary thermometer. Therefore, electronic temperature measurement is adopted, and a sensor 7 and a display 6 are installed on the calorimeter to read the temperature of the system.

[0066] The actual operation takes the following two cases as examples:

[0067] (1) When the calorimeter contains high-temperature water and the metal to be tested 9 as a high-temperature system, the temperature of the high-temperature system is generally about 70°C. After the initial temperature is measured, low-temperature water needs to be added to the calorimeter. The method is to open the rubber plug 8, use the water injection cylinder 11 to inject an appropriate amount of room temperature water (about 20°C) into the inner cylinder 1 through the cylindrical hole 41, and then quickly press the rubber plug 8 to close the system, read the final temperature of the system after equilibrium on the display 6, measure the mass of each relevant object, and substitute all known quantities into the thermal equilibrium formula <1> , the specific heat capacity of the metal 9 to be tested can be calculated.

[0068] (2) When the calorimeter contains low-temperature metal 9 to be tested (or low-temperature metal 9 to be tested plus low-temperature water), the low-temperature metal 9 to be tested can be directly set to room temperature as the initial temperature of the system; if the inner tube 1 contains low-temperature metal 9 to be tested plus water, the initial equilibrium temperature of the system can be measured by the sensor 7 and the display 6, and then the water injection cylinder 11 is used to inject an appropriate amount of high-temperature water (about 70°C) into the inner tube 1 through the cylindrical hole 41, and then the rubber plug 8 is quickly pressed down to close the system, and the final temperature of the system after equilibrium is read on the display 6, and then the mass of each related quantity is measured, and all known quantities are substituted into the heat balance formula. <1> , the specific heat capacity of the metal 9 to be tested can be calculated. The high-temperature water is pre-added into the water injection cylinder 11, and the water injection cylinder 11 is placed in a heater filled with high-temperature water to maintain the temperature, and the temperature is monitored by a thermometer. When the water injection cylinder 11 is taken out to inject water into the calorimeter, the water temperature at this time is the temperature of the high-temperature water.

[0069] In the above-mentioned actual measurement operation, after measuring the initial equilibrium temperature of the system, in the process of adding water (high-temperature water or low-temperature water) into the system, there is no need to open the cylinder cover 4 of the calorimeter, and only a very small cylindrical hole 41 is connected to the outside, which greatly reduces the area of ​​heat dissipation of the high-temperature liquid to the environment; at the same time, because the rubber plug 8 is opened and closed quickly, the time used to open and close the rubber plug 8 is much shorter than the time to open and close the cylinder cover 4 (the cylinder cover 4 is also equipped with an agitator 5, a display 6 and a sensor 7, which is very inconvenient to operate), which greatly reduces the time for the high-temperature liquid to dissipate heat to the environment, so it plays a role in significantly improving the measurement accuracy of the specific heat capacity of the metal.

[0070] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed in the present invention should be covered within the protection scope of the present invention.

Claims

1. An experimental method for accurately measuring the specific heat capacity of metals by injection, characterized in that: A calorimeter body is selected, and an injection mechanism for injecting liquid into the calorimeter body is provided on a cylinder cover (4) of the calorimeter body; The cylinder cover (4) is a stepped cylinder made of engineering plastics. The upper part of the cylinder cover (4) is a cylinder with a larger diameter, and the lower end surface of the stepped part is buckled on the upper edge of the outer cylinder (2). The lower part is a cylinder with a smaller diameter, and the lower end surface of the small cylinder covers the upper edge of the inner cylinder (1). The cylinder cover (4) is provided with a stirrer hole (10), and an injection mechanism for injecting liquid into the inner cylinder (1) of the calorimeter body is provided on the cylinder cover (4) opposite to the stirrer hole (10); The injection mechanism is a cylindrical hole (41) processed on the cylinder cover (4), the cylindrical hole (41) must be within the range of the cylinder cover (4) corresponding to the inner cylinder (1), and a square groove (42) is processed on the side of the cylindrical hole (41); The cylindrical hole (41) connects the space of the inner cylinder 1 of the calorimeter body with the space outside the cylinder cover (4); the cylindrical hole (41) is covered with a rubber plug (8), and the rubber plug (8) isolates the space of the inner cylinder (1) of the calorimeter body from the space outside the cylinder cover (4); The rubber plug (8) is in the shape of a truncated cone, the upper end surface of the truncated cone is connected to the rubber plug seat (82) through a connecting piece (81), the rubber plug seat (82) is embedded in the square groove (42) on the cylinder cover (4), and is fixedly bonded to the square groove (42), and the connecting piece (81) is higher than the upper plane of the cylinder cover (4). When the rubber plug (8) is opened, it automatically stands above the rubber plug seat (82) under the elastic force of the connecting piece (81) and does not block the cylindrical hole (41); The injection mechanism further comprises a water injection cylinder (11); the water injection cylinder (11) is a cylindrical water cylinder, with a scale (13) on the cylinder body, a nozzle (14) at the bottom of the cylinder body, a film (15) on the nozzle (14), and a handle (16) on the upper side of the cylinder body; The experimental method using the above experimental device is: S1: The calorimeter contains high temperature water and the metal to be tested (9) as the high temperature system I ① First mass measurement: Before the experiment, measure the masses of the inner cylinder (1), the stirrer (5), the inner cylinder (1) + high-temperature water, and the metal to be measured (9) respectively; ② Add high temperature water and the metal to be tested (9) into the calorimeter, stir gently with a stirrer (5), and measure the initial temperature T1 of the high temperature system after equilibrium. The value of T1 should be about 70°C; ③ After the initial temperature is measured, low-temperature water needs to be added to the calorimeter, that is, the initial temperature of the low-temperature system II is T2. The method is to open the rubber plug (8), inject a proper amount of room temperature water into the inner cylinder (1) through the cylindrical hole (41) using the water injection cylinder (11), and then quickly press the rubber plug (8) to close the system, and read the final temperature T3 of the system after equilibrium on the display (6); The method of injecting room temperature water into the inner cylinder (1) by using the water injection cylinder (11) is as follows: the nozzle (14) is covered and tightly covered with a film (15), a proper amount of room temperature water is added into the water injection cylinder (11), and the water temperature is monitored with a thermometer, then the nozzle (14) is inserted into the cylindrical hole (41), the film (15) is pierced with a long bamboo stick (17), and the room temperature water in the water injection cylinder (11) is injected into the inner cylinder (1); ④ Second mass measurement: After the experimental operation is completed, measure the mass of the inner cylinder (1) + agitator (5) + metal to be tested (9) + high-temperature water + low-temperature water, and the mass of the low-temperature water can be obtained after calculation; ⑤ Calculate the heat capacity C of the mass of the relevant substance I , C II , where C I The specific heat capacity of the unknown metal to be measured (9) is included; ⑥ Substitute all known quantities into the heat balance equation (1) to calculate the specific heat capacity of the metal to be tested (9); S2: The calorimeter contains a low-temperature metal to be tested (9) or a low-temperature metal to be tested (9) plus low-temperature water as a low-temperature system II ① First mass measurement: Before the experiment, measure the masses of the inner cylinder (1), the stirrer (5), the inner cylinder (1) + low-temperature water, and the metal to be tested (9) respectively; ② If there is only the metal to be tested (9) in the inner cylinder (1), it can be directly set to room temperature, that is, the initial temperature T2 of system II; if the metal to be tested (9) at low temperature is added with water in the inner cylinder (1), the initial equilibrium temperature T2 of the system can be measured by the sensor (7) and the display (6); ③ Use the water injection cylinder (11) to inject a proper amount of high-temperature water with a temperature of T1 into the inner cylinder 1 through the cylindrical hole (41), then quickly press down the rubber plug (8) to seal the system, and read the final temperature T3 of the system after equilibrium on the display (6); The method of injecting high-temperature water into the inner cylinder (1) with the water injection cylinder (11) is as follows: the nozzle (14) is covered and tightly covered with a film (15), the water injection cylinder (11) is placed in a container filled with high-temperature water, and a proper amount of high-temperature water is added into the water injection cylinder (11), the water temperature is monitored with a thermometer, and the temperature is maintained at T1. When water needs to be injected into the inner cylinder (1), the nozzle (14) is inserted into the cylindrical hole (41), and the film (15) is pierced with a long bamboo stick (17). After the film (15) is broken, it quickly shrinks on the edge of the nozzle (14), and the high-temperature water in the water injection cylinder (11) is quickly injected into the inner cylinder (1); ④ Second mass measurement: After the experiment is completed, the mass of the inner cylinder (1) + the stirrer (5) + the metal to be tested (9) + water (including high-temperature water and low-temperature water) is measured. The mass of the high-temperature water can be obtained by calculation. If there is only the metal to be tested (9) but no low-temperature water in the inner cylinder (1) before mixing, the mass of the water measured after the experiment is completed is all the mass of the high-temperature water; ⑤ Calculate the heat capacity C of the mass of the relevant substance I , C II , where C II The specific heat capacity of the unknown metal to be measured (9) is included; ⑥ Substitute all known quantities into the heat balance equation (1) to calculate the specific heat capacity of the metal to be tested (9).

2. The experimental method for accurately measuring the specific heat capacity of metals by injection according to claim 1, characterized in that: The water injection cylinder (11) is made of a plastic material that can withstand relatively high temperatures, and the film (15) is made of a rubber material that has good elasticity and can withstand relatively high temperatures.

3. The experimental method for accurately measuring the specific heat capacity of metals by injection according to claim 1, characterized in that: The rubber plug (8), the connecting piece (81) and the rubber plug seat (82) are all made of a rubber material with good elasticity and are integrally formed.

4. The experimental method for accurately measuring the specific heat capacity of metals by injection according to claim 1, characterized in that: The diameter of the cylindrical hole (41) is 10-15 mm.

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