What are the characteristics of the following sets of gas generators? Need a little more details Tha

The three sets of devices are suitable for the reaction of solid and liquid substances that do not need to be heated, such as the reaction of zinc and dilute hydrochloric acid to produce hydrogen, the reaction of calcium carbonate and dilute hydrochloric acid to produce carbon dioxide, etc. The form of the solid of the first and second sets of devices can be unlimited, which can be either powder or block; The three sets of units are only suitable for bulk solid-liquid reactions. The first is a simple device that adds solids and then liquids, and then quickly plugs a single-hole plug to collect gases.

The second set of devices uses a long-neck funnel, and the lower end of the funnel needs to be immersed below the liquid level when adding liquid, so that more liquid is added, which is not suitable for a very violent reaction, and the gas is produced too quickly and is difficult to collect, such as the action of manganese dioxide powder and hydrogen peroxide. The third set of devices is a simple device of Qipu generator, which can be used at any time, shut down and stop, and must use a block solid to react with a liquid, if it is a powdery solid, it will leak from the small hole of the plastic sheet, and the solid and liquid are always in contact with the reaction, and the reaction cannot be terminated at any time. The principle is:

Put the block solid on the empty plastic sheet, insert the long neck funnel, add the liquid until the liquid is in contact with the solid, the reaction produces gas, when the gas is not needed, close the water stop, the pressure in the test tube increases due to the continued generation of gas, so that the liquid under the plastic sheet enters the long neck funnel, the solid liquid is separated, and the reaction is terminated.

All three are gas generating devices in which liquids and solids react.

The first liquid and solid are both quantitative, the reaction cannot be controlled, and it is difficult to replenish the raw material (opening the rubber stopper will mix in the air magazine).

The second solids are quantified, and the liquid can continue to be added as needed.

The third can freely control the reaction, open the water stop, and the liquid of the scene funnel flows into the test tube to make the liquid level rise to contact with the solid and start to generate gas; At this point, if the water stop clamp is closed, the gas generated by the continued reaction will press the liquid back into the long-neck funnel, the liquid level will drop, and the solid will no longer be in contact, and the reaction will stop.

The third case mentioned in 2l that powdered solids cannot be used can be solved by filter paper, etc., of course, solid particles are generally used.

Solid-to-solid heating, a device for "heating potassium permanganate in the laboratory to produce oxygen".

At room temperature, solids react with liquids and use "hydrogen peroxide in the laboratory to produce oxygen".

Collection device: There are only three types of junior high school chemistry:

Drainage method (collection of gases that are poorly dissolved in water).

Upward air exhaust method (collecting gases that are denser than air).

Downward air exhaust method (collecting gases that are less dense than air).

The basis is as follows:It depends on the state of the reactants and the reaction conditions. The choice of the generator for the production of gases in the laboratory is based on the state of the reactants and the conditions of the reaction.

The laboratory preparation method of gas is mainly compared and summarized from the aspects of drugs, reaction principles, generating devices, collection devices, inspections, inspections and precautions for experimental operation, and the general ideas and methods of laboratory gas production are summarized.

Introduction:

In a chemical reaction, the substances that can participate in the reaction are called reactants, which refer to the substances that can be consumed in a chemical reaction. Solvents and catalysts involved in chemical reactions are not counted as reactants.

When writing such ion equations, it is necessary to first find out the ratio of the amount of reactant species, and if the ratio relationship is not told, the order of dropwise addition. Generally speaking, there is not enough reactant in the dropper at the beginning of the dropper, and there is too much reactant in the Erlenmeyer flask (or reaction vessel such as a beaker).

The collection device is based on whether the density of the gas (generally compared with air) is smaller than that of the upward air exhaust method, and vice versa, whether it can be dissolved in water (reminder that the last air to be collected is to collect carbon dioxide, because carbon dioxide is slightly soluble in water). There are two methods of collecting oxygen: upward air exhaust and drainage.

In the case of liquid-to-liquid reactions or liquid-to-solid reactions, a device consisting of a long-necked funnel and an Erlenmeyer flask is used, and in the case of solids and solids, a test tube is sufficient. Therefore, the first generator is used in the preparation of hydrogen peroxide, and the second type is used for potassium permanganate.

The generator is selected based on the state of the reactants and the reaction conditions. If the state of the reactants is solid, and the reaction conditions need to be heated, the device shown in Figure 1 (oxygen production device) is selected; If the reactants are solid or liquid, and the reaction conditions do not need to be heated, the device shown in Figure 2 or Figure 3 (hydrogen or carbon dioxide production unit) is used.

1. The state of the reactants.

2. Reaction conditions.

1.state of reactants (solid, liquid); 2.Reaction conditions (room temperature, heating) supplement: the idea of preparing gas in the laboratory, the principles of designing experiments and the factors that should be considered in the selection of gas collection devices:

Ideas:1Select the appropriate reaction, reactants, reaction conditions, and reaction rate; 2.Selection of appropriate experimental setup; 3.Choose a reasonable gas inspection and full inspection method.

Principles: economical (i.e. low cost), environmentally friendly, and economical of medicines.

Factors to consider when choosing a gas collection device:1solubility of the prepared gas in water; 2.whether the gas produced can react with water; 3.The magnitude of the difference in the density of the prepared gas compared to air.

We hope you find the above helpful

Gas generators.

A device used to generate gas in a laboratory.

There are two commonly used types, one is O2 type, which is heated by solid and solid mixture, and the other is H2 type, which is the reaction between solid and liquid.

Gas collection device.

Drainage gas collection method: suitable for gases that are difficult to dissolve in water or not easily soluble in water and do not react chemically with water. The gas collected by this method is relatively pure; When a large bubble emerges from the edge of the mouth of the gas collector cylinder, it indicates that the gas has been collected.

Upward air exhaust method: It is suitable for gases that are denser than air and do not react with any components in the air under the same conditions. During operation, attention should be paid to extending the catheter mouth close to the bottom of the gas collection cylinder, so as to facilitate the exhaustion of the air in the gas collection cylinder as soon as possible.

At the same time, the mouth of the gas collection cylinder should be covered with a glass sheet to stabilize the airflow. The gas collected by this method is relatively dry, but the purity is poor, and it needs to be filled.

Downward air exhaust method: It is suitable for gases that are less dense than air and do not react with any components in the air under the same conditions. During operation, attention should be paid to extending the catheter mouth close to the bottom of the gas collection cylinder, so as to facilitate the exhaustion of the air in the gas collection cylinder.

The gas collected by this method is relatively dry, but the purity is poor, and it needs to be filled.

Pay attention to the problem when using potassium permanganate to produce oxygen:

The mouth of the test tube should be slightly inclined downward to prevent the water in the drug from turning into water vapor after being heated, and then condensing into water droplets and flowing back to the bottom of the test tube, so that the test tube will burst.

The trachea should not be too long into the tube, as long as the rubber plug is exposed a little, so that the gas can be easily exported.

The drug should not be gathered at the bottom of the test tube, but should be spread flat at the bottom of the test tube so that it is evenly heated.

The iron clamp should be clamped about 1 3 places away from the mouth of the test tube.

The outer flame of the alcohol lamp should be heated at the drug site. When heating, preheat first, that is, move the alcohol lamp back and forth under the test tube to heat the test tube evenly, and then heat it in front of the drug site.

When collecting oxygen by drainage, it is not advisable to collect oxygen immediately if there are bubbles coming out of the catheter orifice. Because it is air that is initially discharged, it can only be collected when the bubbles emerge evenly and continuously.

When heating potassium permanganate to produce oxygen, do not forget to put a ball of soft cotton at the mouth of the test tube, so as to prevent small particles of potassium permanganate from entering the trachea and blocking the trachea.

Don't forget to check the airtightness of the device before starting the experiment.

At the end of the experiment, remove the air duct from the sink and remove the alcohol lamp to prevent water from backing up and bursting the tube at the bottom of the tube.

The cylinder that collects the oxygen should be covered with a glass sheet and placed on the table (because oxygen is denser than air).

The device for producing gas in the laboratory includes two parts: the generating device and the collection device The selection of the generating device is related to the state and reaction conditions of the reactants If the reactants are solid + liquid reactions, they do not need to be heated, and they belong to the solid-liquid normal temperature type to produce gas; The reactants are all solids and need to be heated, so they are solid heating types, and a device with a heating device such as an alcohol lamp needs to be selected

When selecting the collection method for preparing gases in the laboratory, the selection of the collection method is based on: generally considering the density and solubility of the gas, the gas that is insoluble in water or not easily soluble in water and does not react with water can be collected by drainage method; Gases that are denser than air (that cannot react with components in the air) can be collected by the upward air exhaust method, and gases that are less dense than air (which cannot react with components in the air) can be collected by the downward air exhaust method

Answer: The state of the reactants; reaction conditions; Solid heating type; Solid-liquid normal temperature type; Density; Solubility; drainage method; Upward exhaust air method collection; Downward exhaust air method collection

1.state of reactants (solid, liquid); 2.Reaction conditions (room temperature, heating) supplement: the idea of preparing gas in the laboratory, the principles of designing experiments and the factors that should be considered in the selection of gas collection devices:

Ideas:1Select the appropriate reaction, reactants, reaction conditions, and reaction rate; 2.Selection of appropriate experimental setup; 3.Choose a reasonable gas inspection and full inspection method.

Principles: economical (i.e. low cost), environmentally friendly, and economical of medicines.

Factors to consider when choosing a gas collection device:1solubility of the prepared gas in water; 2.whether the gas produced can react with water; 3.The magnitude of the difference in the density of the prepared gas compared to air.

We hope you find the above helpful

Water solubility (how much solubility there is, whether it can be collected by draining gas collection method), specific gravity (exhaust gas collection method for heavier or lighter gases than air), reaction conditions (can react at room temperature, use a general large test tube, Qipu generator, need to heat a flask, etc.), chemical properties of the gas (generally need to dry, what desiccant to choose, concentrated sulfuric acid for general acid gas, calcium oxide, alkaline lime for alkaline gas, etc., absorbent selection for tail gas, etc.).

The state of the reactants, and whether they are shut down or not.

Design of experimental setup: design the device according to the state of the drug and the reaction principle, as well as the reaction conditions. The device design should be simple and easy to control and operate.

If it's a junior high school it's easier:

1. Reactant state;

2. Whether heating is required.

The state of the reactant and the reaction conditions, and the intensity of the reaction.