Chemistry CO2 is produced in a laboratory

Laboratory-made CO2 is prepared by reacting marble with dilute hydrochloric acid.

With the upward air exhaust method, a match can be lit in the gas collector cylinder, and if the fire is extinguished, it will be filled with gas. As for the dry gas, CO2 can be used as an acid gas, and it can be dried with an acidic desiccant such as concentrated sulfuric acid.

Collect CO2 by the upward exhaust air methodIt's hard to say what's going on. Because CO2 is colorless and odorless. However, you can use a lit wooden strip to place it on the mouth of the gas collector. If it goes off, it proves that the collection is full...

To get dry CO2 gas. It is generally dried by concentrated sulfuric acid.

Two one is CaCO3 + 2HCl = = = CaCl2 + H2O + CO2

The other is CAC03 = high temperature = CA0 + CO2 (the conditions are too high, and I usually don't do experiments in class).

Under normal circumstances, you can't see any obvious phenomenon, to verify whether the collection is full, you need to light the wooden strip to put it at the mouth of the gas collection bottle, if the wooden strip is extinguished, it means that the collection is full.

To dry carbon dioxide gas, it is necessary to use a desiccant that cannot react with it, such as concentrated sulfuric acid.

Nothing. But the fire placed on the mouth of the bottle will be extinguished.

Dry with concentrated sulfur or other acidic desiccant.

Any gases that have been washed with water are not dry and must be strictly dried.

To produce CO2 in the laboratory, C should be collected by the upward exhaust air method

It can be heated with marble and dilute hydrochloric acid solution or at high temperature (marble common name: calcium carbonate).

Each gas has its own properties.

N2 can not be burned, through the dry N2, generally is the O2 in the exhaustion device, sometimes when measuring CO2 can also be passed into N2, the CO2 in the exhaustion device, in the generated CO2 is the reaction obtained, it is possible to draw inferences, and N2 is pollution-free, simple and easy to obtain properties can also be written.

CO, mainly looking at the C carbon element, its characteristics do not support combustion, and it is also possible to exhaust O2 for example, CO+CuO=CO2+Cu

If O2 is not ruled out, 2 CO+O2=2CO2 will change the mass of CO2 measured, and the measured data will not be accurate. Of course, there are other ways to rank CO2, but here are just examples.

O2, the principle is the same, there will generally be O2 in the reactants, and the impurity gas will be discharged.

Speaking of NH3, NH3 is alkaline when dissolved in water, and can neutralize acidic solutions if it does not affect other reactions. Something to consider.

Laboratory preparation of carbon dioxide.

1. Drug: dilute hydrochloric acid and marble (or limestone, the main ingredient is CaCO3).

2. Condition: room temperature.

3. Principle: CaCO3+2HCl==CaCl2+H2O+CO2

CaCO3 + 2HCI = = CACI2 + H2O + CO2 (gas).

Reaction with marble or limestone with dilute hydrochloric acid.

caco3+2hcl=cacl2+h2o+co2↑

caco3+2hcl=cacl2+co2↑+h2o

CaCO3 + 2HCl = CaCl2 + H2O + CO2 (gas arrow).

Chemical equation: CaCO3 +2HCl=CaCl2 +CO2 +H2O

The ionic equation is: CaCO3 +2H+ = Ca2+ +CO2 +H2O

A chemical equation, also known as a chemical reaction equation, is a formula that uses a chemical formula to represent a chemical reaction between different substances. Chemical equations reflect objective factual evidence.

Therefore, there are two principles to be observed in writing chemical equations: first, they must be based on objective facts; Second, it is necessary to abide by the three conservation laws, namely: the law of conservation of mass, the law of conservation of charge, and the law of conservation of materials.

This method is suitable for common chemical equations that are not very difficult. For example, in the reaction formula of kclo kcl+o, the number of oxygen atoms on the right is 2, and the left is 3, then the least common multiple is 6, so the coefficient before kclo should be matched with 2, and the coefficient before o should be matched with 3, and the formula becomes: 2kclo 2kcl+3o.

Since the number of potassium atoms and chlorine atoms on the left becomes 2, the coefficient of 2 should be matched before KCL, ** is changed to equal sign, and the conditions can be indicated

2kCl ==2kCl+3O (The reaction conditions are manganese dioxide catalysis and heating.) "mno" is written above the equal sign; "Heating" is written below the equal sign, and the Greek letters delta " can be used instead).

Solution: NaCl + H2SO4 (concentrated) ==NaHSO4 + HCl (gas) HCl (concentrated) + H2SO4 (concentrated) ==HCl (gas) + H2SO4 (dilute) The method is a physical change (please don't have my answer, thank you).

2NH4Cl+Ca(OH)2 = The condition is heating, i.e. " ".

cacl2+2nh3↑+2h2o．

caco3+2hcl＝cacl2+h2o+co2↑

Problem solving ideas: According to the steps of laboratory carbon dioxide production, tenants: even check and receive, analyze and answer

The operation steps of carbon dioxide production in the laboratory are: connect (connect the instrument, connect the instrument as required) check (check the air tightness of the device) add (add solid drug marble) pour (inject acid into the long-neck funnel) collect (collect by upward exhaust air method).

Therefore, the order of operation is: (2) (1) (4) (3) (5) Therefore, B 10 is selected, and there are generally five steps to prepare CO2 in the laboratory;

1) Check the air tightness of the device (2) Connect the instrument as required (3) Inject acid into the long-neck funnel (4) Roll into a small piece of marble into the large mouth bottle (5) Collect gas, the following operation sequence is correct ( ).

a．（1）（2）（3）（4）（5）

b．（2）（1）（4）（3）（5）

c．（1）（4）（2）（3）（5）

d．（2）（3）（4）（1）（5）

How to produce carbon dioxide in the laboratory, I will share with you the experience below.

CaCO3 2HCl=CaCl2+H2O+CO2 protocol. 1."Check": Check the airtightness of the device.

2."Packing": Fill the marble from the mouth of the Erlenmeyer bottle and tighten the stopper.

3."Add": Add dilute hydrochloric acid from the long-neck funnel (or separating funnel).

4."Receive": Collect gas.

5."Full": Put a burning wooden strip at the mouth of the gas collection cylinder, and the wooden strip is extinguished to prove that the collection is full.

Carbon dioxide is collected by the upward exhaust air method (because carbon dioxide is denser than air). Carbon dioxide cannot be collected by draining (because carbon dioxide is soluble in water).

Precautions for the device: The catheter of the generating device can be exposed to the plug, and it cannot be extended too long; The lower end of the long-neck funnel should be below the liquid level.

Precautions: When collecting carbon dioxide by upward exhaust method, the catheter should extend into the bottom of the gas collection cylinder.

Here's how to make carbon dioxide in the lab:

1.Carbon dioxide is prepared in the laboratory, and it reacts with dilute hydrochloric acid with marble or limestone, their main component is calcium carbonate, and the products are calcium chloride, water and carbon dioxide, and the equation is: CaCO3+2HCl, CaCl2+H2O+CO2.

2.Carbon dioxide can be dissolved in water, react with water to form carbonic acid, can not be collected by drainage method, because the density is greater than air, can be collected by upward air exhaust method; When testing carbon dioxide, the properties of calcium carbonate precipitate are generated by the reaction of carbon dioxide and calcium hydroxide, and the prepared gas is passed into the clarified lime water, if the lime water becomes muddy, the gas is carbon dioxide.

Precautions for laboratory-produced CO2:

1.Dilute sulfuric acid should not be used, because dilute sulfuric acid reacts with calcium carbonate to form calcium sulfate that is slightly soluble in water, which will cover the surface of calcium carbonate and prevent the reaction from proceeding.

2.Concentrated hydrochloric acid cannot be used, because concentrated hydrochloric acid is volatile and cannot obtain pure carbon dioxide gas.

3.Sodium carbonate cannot be used instead of limestone because the reaction is too violent and the resulting gas is difficult to collect. The speed of the reaction rate is related to the mass fraction of the reactants and the contact area.

The larger the contact area of the reactants, the larger the mass fraction of the reactants, the faster the reaction rate, and vice versa, the slower.

1. Chemical reaction and equation for the preparation of carbon dioxide:

The most commonly used method is to react an acid with a carbonate, such as sulfuric acid with calcium carbonate. The reaction equation is: H2SO4 + CaCO3 CaSO4 + H2O + CO2. In the reaction, carbon oxide is released in the form of a gaseous product.

2. Ammonium bicarbonate decomposition is used to produce carbon dioxide

Ammonium bicarbonate can be decomposed by heat to produce carbon dioxide gas. The reaction equation is: NH4HCO3 NH3+H2O+CO2. This method is relatively simple and does not require the use of strong acids, so it is often used in the laboratory.

3. Sodium carbonate reacts with acid to produce carbon dioxide

Acids can react with sodium carbonate to form carbon dioxide gas. Commonly used acids are hydrochloric acid, sulfuric acid, etc. The reaction equation is: 2HCl+Na2CO3 2NaCl+H2O+CO2.

4. Use dry ice to produce carbon dioxide

Dry ice is solid carbon dioxide that can be turned into a gas by heating. When dry ice is heated, it is directly converted into carbon dioxide gas. This method is often used for special laboratory needs.

5. Other methods of producing carbon dioxide:

Other methods can be used in the laboratory to produce carbon dioxide, such as the reaction of sodium hydroxide and acid. Choosing the right method to produce carbon dioxide requires a choice based on experimental needs and conditions.

Expand your knowledge:

Carbon dioxide is a colorless, odorless gas with the chemical formula CO2. It is widely found in nature and is one of the atmospheric components of the earth. Carbon dioxide is often used as a gas source in laboratories, and is also used as a reactant and product in some chemical experiments and industrial processes.

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The equation for the production of carbon dioxide in the laboratory:

1. The chemical reaction equation of high-temperature calcined limestone: caco = cao + co (the condition is high temperature).

2. The chemical reaction equation between marble or limestone (the main component is CACO) and dilute hydrochloric acid: CACO +2HCl=CaCl +HO+CO

3. The chemical reaction equation of baking soda (the main ingredient is sodium bicarbonate) and white vinegar: nahco + ch cooh = ch coona + h o + co

Other preparation methods:

1. Fermentation gas ** method.

The carbon dioxide gas produced in the process of ethanol fermentation is produced, which is washed, impurities removed and compressed to obtain carbon dioxide gas.

2. By-product gas ** method.

In the production process of ammonia, hydrogen and synthetic ammonia, there is often a decarburization (i.e., removal of carbon dioxide in the gas mixture), so that the carbon dioxide in the mixed gas can be absorbed under pressure and heated and desorbed under reduced pressure to obtain high-purity carbon dioxide gas.

3. Adsorption expansion method.

Generally, the by-product carbon dioxide is used as the raw gas, and the high-purity carbon dioxide is extracted from the adsorption phase by adsorption expansion method, and the product is collected by a cryogenic pump; It can also be obtained by adsorption distillation method, which uses silica gel, 3A molecular sieve and activated carbon as adsorbents to remove some impurities, and high-purity carbon dioxide products can be prepared after distillation.

4. Charcoal kiln method.

Carbon dioxide is obtained by refining the gas obtained from the degassing of carbon kiln kiln bie and methanol cracking. <>

The chemical equation for the preparation of carbon dioxide in the laboratory is CaCO3 2HCl==CaCl2 H2O CO2, and the drugs used to produce carbon dioxide in the laboratory are dilute hydrochloric acid and marble (or limestone, the main component is CaCO3), and the conditions are room temperature. Precautions for laboratory-produced carbon dioxide.

1. The preparation of CO2 cannot be reacted with marble (or limestone) with dilute sulfuric acid, because the reaction will occur: CaCO3 H2SO4==CaSO4 H2O CO2, generated. CaSO4 is slightly soluble in water, precipitated in solution, and wrapped around the outside of marble (or lime water), hindering the further development of the reaction.

2. Concentrated hydrochloric acid is generally not used for the preparation of CO2, because it volatilizes HCl gas, which makes the collected CO2 impure.

3. Substances that can react with dilute hydrochloric acid to form CO2 include Na2CO3, K2CO3, etc.

Laboratory CO2 production device.

Depending on the fact that dilute hydrochloric acid is a liquid, limestone is a bulk solid, and the reaction is carried out at room temperature, the same three sets of equipment as the laboratory H2 can be used.

Full: Use a burning wooden strip to place it at the mouth of the gas collection cylinder, and the wooden strip is extinguished to indicate that it is full.