CN214428212U

CN214428212U - Alkane substitution reaction demonstration device

Info

Publication number: CN214428212U
Application number: CN202120367659.6U
Authority: CN
Inventors: 颜乐; 冯舒晴
Original assignee: Fuan No1 Middle School Fujian Province; Fujian Education Equipment And Infrastructure Center
Current assignee: Fuan No1 Middle School Fujian Province; Fujian Education Equipment And Infrastructure Center
Priority date: 2021-02-09
Filing date: 2021-02-09
Publication date: 2021-10-19
Anticipated expiration: 2031-02-09

Abstract

The utility model relates to an alkane substitution reaction demonstration device, which comprises a horizontally arranged base; two sides of the middle part of the upper end of the base are provided with placing grooves downwards in mirror symmetry; a vertical hollow placing bracket is placed in each placing groove; a flask is placed in each placing support; a plug is sealed at the bottle mouth of the flask; a light source is vertically arranged at the upper end of the base behind each placing groove; the light emitted by the light source is right opposite to the flask body of the flask; the upper end of the outer side of one of the placing grooves is detachably fixed with a cover body; the cover body is made of opaque materials. The demonstration device for alkane substitution reaction provides a scientific, practical, simple in structure and convenient in operation demonstration experiment device for halogenated hydrocarbon properties. The alkane substitution reaction demonstration device adopts a liquid-liquid mixing form of aviation kerosene and liquid bromine, is simple and convenient to operate, easy to control and obvious in phenomenon, can be used for a hall grouping experiment, and basically has no bromine leakage.

Description

Alkane substitution reaction demonstration device

Technical Field

The utility model relates to an alkane substitution reaction presentation device belongs to chemical test device technical field.

Background

The chemical demonstration experiment teaching is a source of chemical charm and arouses the learning interest of students, is a basic method for learning chemistry, and has important significance for forming chemical concepts for the students, understanding and consolidating chemical knowledge, culturing scientific attitudes of observation ability, thinking ability and fact of the students, obtaining skilled experimental skills and improving the quality of chemical teaching. The demonstration experiment device is a material basis of chemical demonstration experiment contents and methods and plays a key role in the success of chemical demonstration experiments. The beginning of learning and learning organic compounds by the students is that the substitution reaction of alkane is the first important organic reaction. The substitution reaction is a teacher demonstration experiment adopting the methane and chlorine illumination reaction, and has the problems of complicated operation, difficult control, unobvious phenomenon, toxic gas leakage pollution, non-rigorous product verification and the like, so that the teaching is generally carried out by adopting a playing video to substitute the demonstration experiment, and the learning effect and interest of students are greatly reduced. We seriously lack a demonstration device which is simple and can fully show substitution reaction for students, and an experimental device suitable for the students to operate.

SUMMERY OF THE UTILITY MODEL

In order to overcome the problem, the utility model provides an alkane replaces reaction presentation device, this alkane replaces reaction presentation device provides a nature demonstration experimental apparatus of scientific, practical, simple structure, convenient operation's halohydrocarbon.

The technical scheme of the utility model as follows:

a demonstration device for alkane substitution reaction comprises a horizontally arranged base; two sides of the middle part of the upper end of the base are provided with placing grooves downwards in mirror symmetry; a vertical hollow placing bracket is placed in each placing groove; a flask is placed in each placing support; a plug is sealed at the bottle mouth of the flask; a light source is vertically arranged at the upper end of the base behind each placing groove; the light emitted by the light source is right opposite to the flask body of the flask; the upper end of the outer side of one of the placing grooves is detachably fixed with a cover body; the cover body is made of opaque materials.

Further, the placing support comprises a bell mouth with a funnel-shaped structure with a large upper part and a small lower part and a base which is fixed at the lower end of the bell mouth and is in a cylindrical structure; a plurality of horizontal baffles are uniformly fixed on the inner periphery of the lower end of the base at intervals; two adjacent baffles are spaced by a cutting groove; one end of the baffle, which is far away from the base, is an arc-shaped edge; the arc edges of all the baffles surround to form a middle hole; the periphery of the flask body is attached to the upper end face of the baffle, and the lower part of the flask body is accommodated in the middle hole.

Further, the cover body comprises a shell which is in a vertical hollow cylindrical structure and a cover plate which is fixed at the upper end of the shell; the shell is made of a lightproof material, and the lower end of the shell is detachably fixed at the upper end of the outer side of the placing groove; the cover plate is made of transparent materials, and the middle part of the cover plate is provided with an avoidance hole for the bottle mouth of the flask to penetrate out.

Furthermore, an annular flange is fixed on the outer side of the upper end of the horn mouth; the periphery of the flanging is attached to the inner periphery of the placing groove.

The utility model discloses following beneficial effect has:

1. the demonstration device for alkane substitution reaction provides a scientific, practical, simple in structure and convenient in operation demonstration experiment device for halogenated hydrocarbon properties.

2. The alkane substitution reaction demonstration device adopts a liquid-liquid mixing form of aviation kerosene and liquid bromine, is simple and convenient to operate, easy to control and obvious in phenomenon, can be used for a hall grouping experiment, and basically has no bromine leakage.

3. The alkane substitution reaction demonstration device is simple and convenient to operate, easy to control and obvious in phenomenon, the possibility of hands-on experiments of students is greatly improved, and the interests of the students in learning chemistry and exploring knowledge are well stimulated.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Fig. 2 is a top view of fig. 1.

Fig. 3 is a schematic view of the internal structure of the base.

Fig. 4 is a schematic view of the overall structure of the placing support.

Fig. 5 is a top view of fig. 4.

Fig. 6 is a cross-sectional view of a stent being placed.

The reference numbers in the figures denote:

1. a base; 11. a placement groove; 12. a light source; 2. placing a bracket; 21. a bell mouth; 22. a base; 23. flanging; 24. A baffle plate; 25. a middle hole; 26. grooving; 3. a flask; 31. a plug; 4. a cover body; 41. a housing; 42. a cover plate; 43. Avoiding the hole.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1-6, an alkane substitution reaction demonstration device comprises a horizontally arranged base 1; two sides of the middle part of the upper end of the base 1 are provided with placing grooves 11 downwards in mirror symmetry; a vertical hollow placing bracket 2 is placed in each placing groove 11; a flask 3 is placed in each placing bracket 2; a plug 31 is sealed at the bottle mouth of the flask 3; a light source 12 is vertically arranged at the upper end of the base 1 behind each placing groove 11; the light emitted by the light source 12 is right opposite to the bottle body of the flask 3; the upper end of the outer side of one of the placing grooves 11 is detachably fixed with a cover body 4; the cover 4 is made of a light-tight material.

According to the above description, the alkane substitution reaction demonstration device mainly comprises a base 1, a placing support 2, a flask 3 and a cover body 4. The base 1 is used as a supporting carrier, the placing groove 11 is used for placing the placing support 2, and the light source 12 is opposite to the flask 3; a flask 3 is placed in the placing support 2; the cover 4 is placed on one of the placement grooves 11.

In the experimental process, aviation kerosene and liquid bromine are adopted for substitution reaction and liquid-liquid mixed reaction, so that the method is simple and convenient to operate, easy to control, obvious in phenomenon, high in safety, basically free of toxic gas leakage and capable of meeting the requirement of green chemistry.

Further, the placing support 2 comprises a bell mouth 21 with a funnel-shaped structure with a large upper part and a small lower part and a base 22 which is fixed at the lower end of the bell mouth 21 and has a cylindrical structure; a plurality of horizontal baffles 24 are uniformly fixed on the inner periphery of the lower end of the base 22 at intervals; two adjacent baffles 24 are separated by a cutting groove 26; one end of the baffle plate 24 far away from the base 22 is an arc-shaped edge; all the arc edges of the baffle plates 24 surround to form a middle hole 25; the periphery of the bottle body of the flask 3 is attached to the upper end face of the baffle plate 24, and the lower part of the bottle body of the flask 3 is accommodated in the middle hole 25.

In the experimental process, various containers (such as test tubes, beakers, flasks 3 and the like) can be used, the size and the shape of each container are different, and the placing support 2 can achieve a good fixing effect on different containers. The bell mouth 21 is large at the top and small at the bottom, so that the container can enter conveniently; the baffles 24 are arranged at intervals, and a middle hole 25 in the middle can be used for keeping the position of the test tube; when the container is a structure with a large bottom such as a beaker and a flask 3, the bottom of the container is contacted with the upper end of the baffle plate 24, the tail end of the baffle plate 24 is lowered due to the arrangement of the cutting groove 26 and the middle hole 25 so as to support the container, and the container can also be stably supported and fixed.

Further, the cover 4 comprises a housing 41 in a vertical hollow cylindrical structure and a cover plate 42 fixed on the upper end of the housing 41; the housing 41 is made of a light-tight material, and the lower end of the housing is detachably fixed at the upper end of the outer side of the placing groove 11; the cover plate 42 is made of transparent material, and the middle part of the cover plate 42 is provided with an avoidance hole 43 for the bottle mouth of the flask 3 to penetrate through.

Further, an annular flange 23 is fixed on the outer side of the upper end of the bell mouth 21; the outer periphery of the turned edge 23 is attached to the inner periphery of the placing groove 11.

The utility model discloses a theory of operation:

the aviation kerosene is a high boiling point hydrocarbon mixture with 11 to 17 carbon atoms, and the main component is saturated hydrocarbon; liquid bromine is a dark reddish brown liquid at room temperature. The reaction of the two is liquid-liquid reaction. The mechanism of the substitution reaction of the alkane and the halogen simple substance under the illumination condition is a free radical chain reaction, and the three stages of chain initiation, chain growth and chain termination are mainly carried out, and the initiation stage needs external energy supply.

Referring to fig. 1-6, when the alkane substitution reaction demonstration device is used, aviation kerosene is injected into two flasks 3 respectively by using injectors; then, using another syringe, liquid bromine was injected into each of the two flasks 3, and the stopper 31 was closed. At this time, it was observed through the flask 3 that the liquid bromine was mixed with aviation kerosene, and settled to the bottom of the flask 3, and the color was reddish brown after the mixing.

Then, the two flasks 3 were placed in the placing holders 2 of the placing grooves 11, respectively, and the opaque cap 4 was attached to one of the placing grooves 11, and the flask 3 provided with the cap 4 was designated as a bottle a, and the other flask 3 was designated as a bottle B. Light source 12 was then activated to direct light at the body of flask 3 for three minutes. At this time, it can be observed that the color of the mixed liquid in the bottle A is not obviously changed; and a large amount of bubbles are generated in the bottle B, and the color of the mixed liquid gradually becomes light and finally fades. It can be confirmed that the condition generated by the substitution reaction of aviation kerosene and liquid bromine is light irradiation.

Then, the B bottle was opened, concentrated ammonia water was added to the B bottle, and the B bottle was quickly closed. At this time, it can be observed that a large amount of white smoke is generated immediately at the upper part of the bottle B, i.e. the gas generated by the replacement reaction before can be proved to be HBr; then HBr reacts with strong ammonia water to generate NH₄Solid Br. Meanwhile, the bottle body of the bottle B can be obviously heated by touching the bottle B.

The above only is the embodiment of the present invention, not limiting the patent scope of the present invention, all the equivalent structures or equivalent processes that are used in the specification and the attached drawings or directly or indirectly applied to other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An alkane substitution reaction demonstration device, which is characterized in that: comprises a base (1) which is horizontally arranged; two sides of the middle part of the upper end of the base (1) are provided with placing grooves (11) downwards in mirror symmetry; a vertical hollow placing bracket (2) is placed in each placing groove (11); a flask (3) is arranged in each placing bracket (2); a plug (31) is sealed at the bottle mouth of the flask (3); a light source (12) is vertically arranged at the upper end of the base (1) behind each placing groove (11); the light emitted by the light source (12) is right opposite to the bottle body of the flask (3); the upper end of the outer side of one placing groove (11) is detachably fixed with a cover body (4); the cover body (4) is made of a lightproof material.

2. The alkane substitution reaction demonstration device of claim 1, wherein: the placing support (2) comprises a bell mouth (21) which is of a funnel-shaped structure with a large upper part and a small lower part and a base (22) which is fixed at the lower end of the bell mouth (21) and is of a cylindrical structure; a plurality of horizontal baffles (24) are uniformly fixed on the inner periphery of the lower end of the base (22) at intervals; two adjacent baffles (24) are separated by a cutting groove (26); one end of the baffle (24) far away from the base (22) is an arc-shaped edge; the arc edges of all the baffles (24) surround to form a middle hole (25); the periphery of the bottle body of the flask (3) is attached to the upper end face of the baffle (24), and the lower part of the bottle body of the flask (3) is accommodated in the middle hole (25).

3. The alkane substitution reaction demonstration device of claim 1, wherein: the cover body (4) comprises a vertical hollow cylindrical shell (41) and a cover plate (42) fixed at the upper end of the shell (41); the shell (41) is made of a lightproof material, and the lower end of the shell is detachably fixed at the upper end of the outer side of the placing groove (11); the cover plate (42) is made of transparent materials, and the middle part of the cover plate (42) is provided with an avoidance hole (43) for the bottle mouth of the flask (3) to penetrate out.

4. The alkane substitution reaction demonstration device of claim 2, wherein: an annular flanging (23) is further fixed on the outer side of the upper end of the bell mouth (21); the periphery of the flanging (23) is attached to the inner periphery of the placing groove (11).