US3370925A

US3370925A - Method of conducting chemical gas experiments and laboratory apparatus for generating gas

Info

Publication number: US3370925A
Application number: US431408A
Authority: US
Inventors: Gerald E Trueblood
Original assignee: Gerald E. Trueblood
Current assignee: GERALD E TRUEBLOOD
Priority date: 1965-02-09
Filing date: 1965-02-09
Publication date: 1968-02-27
Anticipated expiration: 1985-02-27

Description

Feb. 27, 1968 G. E. TRUEBLOOD METHOD OF CONDUCTING CHEMICAL GAS EXPERIMENTS AND LABORATORY APPARATUS FOR GENERATING GAS Filed Feb. 9, 1965 INVENTOR. 'era/d 5 7/ aeb/00a I A:TTORNEYS United States Patent 3,370,925 METHOD OF CONDUCTING CHEMICAL GAS EX PERIMENTS AND LABORATORY APPARATUS FOR GENERATING GAS Gerald E. Trueblood, 410 Grant St., Geneva, Ill. 60134 Filed Feb. 9, 1965, Ser. No. 431,408 8 Claims. (Cl. 23211) This invention relates generally to a method of and apparatus for conducting chemical gas experiments in a laboratory and more particularly relates to a laboratory method and apparatus for reacting a liquid such as an acid with a specimen such as a metal sample for generating a determinable quantum of gas wherein the metal sample is capsulated within a specimen holder retained in the mouth of a gas-generating tube so that all of the reaction liquid is diffused through the specimen holder as gas is generated and trapped within the tube.

An experiment that has long been performed by chemistry students at the high school and college levels involves putting a small amount of concentrated acid in a gas-measuring tube and then filling the tube to the mouth thereof with water. A piece of metal is held at the mouth and when the tube is inverted in a beaker containing water, the acid diffuses downwardly until it finally reacts with the metal at the mouth to release a gas which is collected for measurement in the gas-measuring tube. by following such procedures with equipment heretofore provided, a problem is presented in keeping the metal at the mouth of the gas-measuring tube in order to react properly with the downward diffusing acid.

In accordance with the principles of the present invention, a small flexible plastic capsule adapted to capsulate a metal specimen is inserted into the mouth of a gasmeasuring tube, and the specimen-holding capsule is characterized by apertures formed in the walls thereof to permit the acid to enter the capsule and to allow the gas generated to leave the capsule. The capsule is retained in press-fit assembly in the mouth of the tube by means of flexible ribs and a plug may be provided which not only insures diffusion of the acid through the capsule, but also facilitates assembly of the specimen holder in the gasmeasuring tube.

It is an object of the present invention, therefore, to provide an improved method of conducting chemical gas experiments in a laboratory with the use of apparatus overcoming the deficiencies of the prior art.

Another object of the present invention is to provide laboratory apparatus for generating gas by the reaction of a metal and an acid wherein the metal specimen may be encapsulated in the mouth of a gas-generating tube.

Yet another object of the present invention is to provide an improved specimen holder adapted to be inserted in the mouth of a gas-measuring tube and which is particularly characterized by means formed therein permitting a reaction liquid to diffuse outwardly from the tube through the specimen holder and for gas generated by the reaction to be captured in the tube.

Many other features, additional advantages and further objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description which follows and the accompanying sheet of drawings in which a preferred structural embodiment of my invention is shown by way of illustrative example and by means of which the novel methods contemplated by the present invention may be effectively practiced.

As shown on the drawings:

FIGURE 1 is an elevational view of a gas-measuring tube in which the specimen holder is assembled in the open mouth thereof;

FIGURE 2 is a somewhat schematic view illustrating the gas-measuring tube of FIGURE 1 inverted and with the end thereof in a beaker of water;

FIGURE 3 is a cross-sectional view taken generally on line III-III of FIGURE 2;

FIGURE 4 is a cross-sectional view taken generally on line IVIV of FIGURE 3; and

FIGURE 5 is an exploded view showing additional details of construction of the specimen holder provided in accordance with the principles of the present invention for use in a gas-measuring tube.

As shown on the drawings:

A gas-measuring tube is shown generally at 10 and comprises a generally cylindrical tube having a body 11 formed with a calibrated scale 12 extending longitudinally along the length thereof from a closed end.13.

Theopposite end of the tube 10 is formed with an opening forming a mouth 14. In accordance with operating procedures, the tube 10 may be charged with a suitable amount of concentrated acid whereupon the tube is filled to the mouth 14 with water. A metal specimen is then placed at the mouth 14 of the tube 10 and the tube is inverted in a beaker containing water so that the downwardly diifusing acid will react with the metal to release a gas collected for measurement in the tube 10.

A. beaker is shown at 16 filled with water to a water level shown at 17 establishing the organization in which the present invention finds particular utility.

It is contemplated by the present invention to provide a specimen holder which more particularly comprises a capsule shown generally at 20 and a plug shown generally at 21.

More specifically, the capsule constitutes a generally cylindrical tube having side walls 22 surrounding an inner bore 23 and having an outer peripheral surface 24.

A plurality of longitudinally extending ribs 26 are formed on the outside surface of the walls 24 and are spaced circumferentially from one another. In the preferred embodiment herein illustrated, there are four ribs 26 spaced from one another in equiangular relationship. The outer diameter of the walls, measured at the outer surface 24, is less than the inner diameter of a standard gas-measuring tube 10. In this connection, it is contemplated that the capsule 20 could be made in at least two different sizes for association with either a 25 milliliter or 50 milliliter gas-measuring tube. The outer diameter of the capsule 20 measured across the outwardly projecting ribs 26 would be approximately equal to the inside diameter of the tube 10.

Each of the ribs or radially outwardly extending projections 26 extends a substantial distance along the length of the walls 24 in the embodiment herein illustrated, through it will be appreciated that other physical forms of ribs or projections could be employed within the spirit and intent of the present invention. In the present embodiment, each rib extends from an end portion 27 at the innermost end of the capsule 20 and terminates in a cir-,

cumferentially continuous collar 28 formed at the end of capsule 20. The collar 28 is of the same outer diameter as the ribs or projections 26 and is adapted to be received It will be noted that when the capsule 20 is inserted into the mouth 14 of the tube 10, an annular space 32 (FIGURE 4) will be left between the outer surface 24 of the capsule 20 and the adjoining inner walls of the tube 10. Accordingly, when the tube is inverted, the liquid contents thereof will freely pass through the apertures 31 into the hollow interior of the capsule 20 provided by the bore 23.

Inwardly of the collar 28, the capsule is characterized by an internally threaded portion 33 which threadedly receives the externally threaded portion 34 of the plug 21. The plug 21 has a generally cylindrical body 36 and a radial end wall 37 from which projects axially a knob 38.

The knob 38 has a neck 39 which joins the main body portion 36 of the plug 21 at a central portion of the end wall 37. At spaced points outwardly of the neck 39, the body 36 of the plug 21 is provided with axially extending difiusion passages 40 which intersect the end wall 37 as well as an end wall 41 at the other end of the body 36.

Both the capsule 20 and the plug 21 are preferably made of a flexible, chemically inert plastic material such as polyethylene. By making the parts of such material, it will be understood that the ribs or projections 26 will be somewhat elastic as will the collar 28. Moreover, the threaded connection between the

threads

33 and 34 can also be conveniently effected.

The tapered nose or conically shaped end portion provided by the Walls 29 on the capsule 20 provide a finder portion for piloting the capsule into the mouth 14 of the tube 10. In practice, therefore, the tube 10 can either be precharged with the requisite amount of reaction liquid such as concentrated acid, and a specimen of metal which is shown in FIGURE 3 at S is inserted through the threaded opening 33 into the bore 23 of the capsule 20, whereupon the capsule is inserted into the tube 10 through the mouth 14. The ribs or projections 26 will slidingly engage the adjoining inside walls of the tube 10 and the circumferentially continuous surface of the collar 28 will seal the adjoining edges of the mouth '14. Either before or after insertion into the tube, the plug 21 may be threaded into the end of the capsule 20. By inserting the plug 21 into the capsule before insertion, the knob 38 may be advantageously used in manipulating the specimen holder and in effecting the insertion thereof into thetube 10.

So inserted, the specimen holder functions to position the metal specimen S directly in the mouth of the tube 10 so that upon inversion of the tube into a beaker of water, the acid will flow down into surrounding relationship to the

walls

22 and 29 of the capsule and will enter the interior of the capsule into the bore 23 via the apertures 31. Upon reaction with the metal specimen S, gas generated by the reaction will be released through the apertures 31 into the gas-measuring tube 10 and upon displacement of the liquid reaction fluid, the liquid will dififuse outwardly through the diffusion passages 40' in the plug 21 and into the beaker 16.

There is thus provided 'an improved method and means for generating gas under safe laboratory conditions. Hazards are eliminated and accuracy in conducting the experiment is insured. Moreover, the specimen holder of the present invention can be economically fabricated from suitable chemically inert materials and the device is simple to use and reliable in practice.

Although various minor modifications might be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.

I claim as my invention:

1. The method of conducting chemical gas experiments in the laboratory which includes the steps of charging a supply of acid into' a gas-measuring tube through the mouth of the tube,

confining a piece of metal in a foraminous specimen holder sized complementally to the mouth of the tube,

inserting the specimen holder into the mouth of the tube in press-fit relationship therewith to retain the specimen in sealed assembly with the tube at the mouth thereof,

inverting the tube with the mouth of the tube into a beaker of water,

and diffusing the acidthrough the specimen holder in reactive relation with the metal to release gas for measurement in the inverted tube.

2'. Apparatus for conducting chemical gas-generating experiments in the laboratory comprising,

a gas-measuring tube having an elongated body portion and an open mouth at one end,

said body portion having a calibrated scale formed thereon for measuring the contents thereof,

and a specimen holder sized to be press-fit in said mouth,

said specimen holder having walls forming a compartment for holding a piece of metal,

the walls of said specimen holder having diffusion passages forrned therethrough, whereby a quantity of acid contained in said tube may be diffused through said passages in reactive relation to metal in said specimen holder when the tube is inverted in a breaker of water.

3. In a laboratory apparatus for generating gas by the reaction ofmetal and acid, the improvement of a capsule made of chemically inert flexible plastic material for insertion into the end of a gas-measuring tube charged with a reactive liquid, said capsule comprising a generally cylindrical body having cylindrical walls,

aplurality of longitudinally extending radially outwardly projecting ribs circumferentially spaced from one another on the peripheral surface of said cylindrical walls,

the outer diameter of said body portion walls being less than the inner diameter of a gasmeasuring tube and the outer diametral dimension measured across said ribs being substantially equal to the inner diameter of the gas-measuring tube,

said ribsbeing sufliciently elastic to adapt said capsule for a sliding press-fit into the mouth of a gas-measuring tube with said walls spaced from the adjoining tube walls,

said body terminating at one end in a convergent longitudinally extending end wall closing one end of the body,

' the other end of said body having an internally threaded mouth opening formed therein through which a specimen adapted to react with said liquid may be inserted for containment in said capsule,

and a plug made of flexible chemically inert plastic material having an externally threaded neck portion threaded into said mouth opening,

said body having a circumferentially continuous end collar for overlying said ribs and sealing in press-fit relationship against the adjoining walls of the gas-measuring tube to close thespace between the walls of the gas-measuring tube and the'capsule, said plug having axially extending diflfusion passages formed therein for diffusing the liquid contents of said capsule outwardly when the gas-measuring tube is inverted in a beaker of water, a said walls of said capsule being formed with openings to direct the reaction liquid from the interior of the gas-measuring tube when inverted through the capsule for reaction with the speci men,

said plug having an axially outwardly projecting knob for manipulating the plug.

4. Laboratory apparatus for reactmg liquid .acid with a metal specimen in generating a determinable quantum of gas, comprising,

a generally tubular laboratory tube closed at one end, open at the other end and formed with a calibrated scale between the opposite ends and adapted to be charged with a quantity of liquid acid when positioned uprightly,

a specimen holder inserted in said tube at its open end comprising a capsule having outwardly extending projections engaging the adjoining side walls of the tube, thereby leaving a space around the capsule,

said capsule having :a compartment formed therein and being open at one end to receive a metal specimen in said compartment,

the walls of said capsule being apertured to form diffusion passages therein communicating the interior of the capsule with the interior of the tube, and a plug threaded into the open end of said capsule and having axially extending diffusion passages formed therein so that when the tube is inverted and the open end thereof placed in a beaker of water the acid in the tube will pass through the diffusion passages in the capsule walls for reaction with the metal specimen and will be displaced through the diffusion passages in the plug when gas is generated and trapped in the inverted tube.

5. Laboratory apparatus as defined in claim 4 and further characterized by said specimen holder having circumferentially continuous sealing means engaging the walls of the tube to insure that .all of the acid in the tube will be directed through the capsule for reaction with the specimen.

6. Laboratory apparatus as defined in claim 5 and further characterized by said specimen holder being made of flexible chemically inert plastic material so that said ribs and said plug Will be sufiiciently elastic to promote press-fit sealing relationships with adjoining parts.

7. Laboratory apparatus as defined in claim 6 and further characterized by said capsule including a tapered convergent end wall forming a finder portion for piloting the capsule into the end of the tube.

8. Laboratory apparatus as defined in claim 7 and further characterized by said plug having a knob extending outwardly in an axial direction for manipulation dur ing insertion and extraction from the tube and the capsule.

References Cited UNITED STATES PATENTS 1,507,060 9/1924 Hayes 23-282 1,518,999 12/ 1924 Miller 23-272.8

FOREIGN PATENTS 954,642 4/ 1964 Great Britain.

MORRIS O. WOLK, Primary Examiner. JAMES H. TAYMAN, JR., Examiner.

Claims

1. THE METHOD OF CONDUCTING CHEMICAL GAS EXPERIMENTS IN THE LABORATORY WHICH INCLUDES THE STEPS OF CHARGING A SUPPLY OF ACID INTO A GAS-MEASURING TUBE THROUGH THE MOUGH OF THE TUBE, CONFINING A PIECE OF METAL IN A FORAMINOUS SPECIMEN HOLDER SIEZED COMPLEMENTALLY TO THE MOUTH OF THE TUBE, INSERTING THE SPECIMEN HOLDER INTO THE MOUTH OF THE TUBE IN PRESS-FIT RELATIONSHIP THEREWITH TO RETAIN THE SPECIMEN IN SEALED ASSEMBLY WITH THE TUBE AT THE MOUTH THEREOF, INVERTING THE TUBE WITH THE MOUTH OF THE TUBE INTO A BEAKER OF WATER, AND DIFFUSING THE ACID THROUGH THE SPECIMEN HOLDER IN REACTIVE RELATION WITH THE METAL TO RELEASE GAS FOR MEASUREMENT IN THE INVERTED TUBE.