How to test oxygen and carbon dioxide, chemistry There are 4 ways to identify oxygen and carbon diox

Two gases are passed into lime water, the turbid one is carbon dioxide, and the unchanged one is oxygen.

Quicklime and water are mixed together first (a chemical reaction occurs: CaO+H2O=Ca(OH)2).

Then pour it into two vessels containing gas.

A chemical reaction occurs: Ca(OH)2 +CO2=CaCO3 +H2O) After a while, if there is turbidity or precipitation in any vessel, it is carbon dioxide in this vessel, otherwise it is oxygen

When you put a spark into the gas, the oxygen is rekindled and the carbon dioxide is quickly extinguished.

I don't need to say it, it's repetitive.

Put the wooden strip with sparks in it, and if it's more violent, the O2 is the CO2 that goes out

There is also Ca(OH)2 to CO2 gas collector cylinders

Common name: clarified lime water

ca（oh）2+co2=caco3+h2o

Mix limestone and water into lime water and let it stand, you can get some clarified lime water. Then the clarified lime water is divided into two bottles of gas, **. If the lime water becomes cloudy, it is CO2, and the other bottle is O2

You first dissolve the lime in the water, and then you put the two gases in the lime water, and the turbid one is carbon dioxide, and the other is oxygen!

When two gases are passed into the clarified lime water, the one that becomes turbid is CO2, and the one that does not change is O2

Experimental process: 1) Add limestone to water to dissolve. Formation of lime water.

Theory: CaO+H2O=Ca(OH)2

2) Then the gas is passed into the lime water, and the white precipitate is carbon dioxide.

Theory: Ca(OH)2 + CO2 = CaCO3 + H2O

Quicklime reacts with water to produce mature lime Ca(OH)2

CO2 passes into the aqueous solution of hydrated lime and will be turbid.

O2 does not react in this way.

1. Stretch a wooden strip with sparks into the bottle, if the wooden strip rekindles, it proves that it is oxygen, and there is no obvious phenomenon to prove that it is CO2.

2. Inject clarified lime water into the bottle. If there is a white precipitate, it proves that it is CO2, and if there is no obvious phenomenon, it proves that it is O2.

3. Inject purple litmus into the bottle, if the test solution turns red, it proves to be CO2, and no obvious change proves that it is O2.

4. Insert a red-hot copper wire, if the copper wire turns black, it proves to be oxygen, and no obvious change proves that it is CO2.

Burning sticks of wood reach out to the mouth of the gas collection cylinder and pass through the scorching copper mesh; The gas-filled test tube was inverted into the NaOH solution, and the clear lime water was passed; There are many more, judging by their nature.

A spark-bearing stick of wood was inserted into the gas collection cylinder, and the oxygen bottle was rekindled.

A flaming stick of wood is inserted into the gas collection cylinder, and the strip extinguishes the bottle of carbon dioxide.

Add a certain amount of clarified lime water to each of the two bottles, **, and the bottle that becomes cloudy is carbon dioxide.

1.With a burning stick, if extinguished, it is carbon dioxide; If it is more prosperous, it is oxygen 2With clarified lime water, there is a precipitation of carbon dioxide (a small amount), and no phenomenon is oxygen 3

With burning magnesium bars, if there is a black substance, carbon dioxide is generated, and if it is white, it is oxygen4With litmus solution, it is carbon dioxide that changes color, and oxygen that does not change color.

1. Carbon dioxide is introduced into the clarified lime water respectively, and the lime water becomes turbid;

2. Add the positive burning magnesium strips respectively, and the black solid is carbon dioxide, and the white solid is oxygen;

3. Carbon dioxide is the carbon dioxide that extends into the burning wooden strip and extinguishes the wooden strip;

4. Extend into the wooden strip with sparks, and it is oxygen that rekindles the wooden strip.

1 Whether the Martian wood strip is rekindled is oxygen, and carbon dioxide is the opposite, 2 It is carbon dioxide that passes into the clarified lime water, and the turbidity is carbon dioxide.

3. Soluble in water, it is carbon dioxide that detects pH as acidic.

4. In the magnesium combustion test, combustion is supported, and a small number of black particles will appear in the carbon dioxide experiment, which is a carbon element, and there is no such phenomenon in the oxygen experiment.

It is oxygen that is rekindled with Martian sticks, and carbon dioxide that is extinguished.

The turbidity at the edge of the clarified lime water is carbon dioxide, the non-phenomenon is that oxygen bubbles out after oxygen is passed into sodium hydroxide, and the absorbed carbon dioxide is put into sulfur powder to ignite, and the blue flame is oxygen, and the carbon dioxide that cannot be lit is carbon dioxide.

Comparison of the properties of oxygen and carbon dioxide.

The sparkled strip is close to the mouth of the bottle, and the oxygen is rekindled and the carbon dioxide is extinguished.

The magnesium band ignites, and it is carbon dioxide that produces a black substance.

When the clarified lime water is introduced, it is carbon dioxide that becomes turbid.

The red-hot copper wire protrudes into two gases, and it is oxygen that turns black.

Wooden strips with Mars.

Burning sticks of wood.

Clarified lime water.

Litmus solution.

Methods for identifying carbon monoxide and carbon dioxide:

First, according to the different densities, they are inflated into the balloon back;

The denser is carbon dioxide. Answer.

secondly, according to the different water solubility, they are respectively passed into the litmus test solution;

Two gases are passed into the purple litmus test solution, the original gas of purple litmus turning red is carbon dioxide, and the original gas that does not change color is carbon monoxide.

third, according to the flammability;

1. Carbon monoxide is carbon monoxide that can burn and produce a blue flame, and carbon dioxide that does not burn.

2. Use the burning wooden strip to stretch into the two gas collection cylinders respectively, if the gas in the bottle is burned, the gas is CO, if the wooden strip flame is extinguished, the gas is CO2.

Fourth, according to the different reductionability, they are respectively passed into the hot copper oxide;

The two gases are passed through the hot copper oxide (mesh) respectively, and the original gas produced by the red object is carbon dioxide, and the original gas without obvious phenomenon is carbon monoxide.

Fifth, according to whether they react with alkali solution, they are respectively passed into the clarified lime water.

The two substances are respectively introduced into the clarified lime water, and the original gas that becomes turbid is carbon dioxide, and the non-phenomenon is carbon monoxide.

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

1.Carbon dioxide is prepared in the laboratory, and it is reacted with dilute hydrochloric acid with marble or limestone, and the main component of their posture 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 precipitation are generated by the reaction of carbon dioxide and calcium hydroxide, and the method is to pass the prepared gas into the clarified lime water, and if the lime water becomes muddy, the gas is carbon dioxide.

Method of testing carbon dioxide: gas is passed into the clarified lime water, if the clarified lime water becomes turbid, the gas is carbon dioxide, and vice versa.

Carbon Dioxide Test Method:

1. Introduce colorless gas into clear lime water. If the solution becomes turbid, it indicates that the gas contains CO.

2. Bromothymol blue aqueous solution can identify carbon dioxide (CO), and the solution changes from blue to green and then to yellow.

Principle of carbon dioxide test for clarified lime water:

Carbon dioxide passes into the clarified lime water and becomes turbid, because carbon dioxide reacts with the clarified lime water to form calcium carbonate precipitation.

The chemical equation is: Co +Ca(OH) = CaCo +H O

Identification method: put the extinguished match into the sealed gas cylinder, if the match is rekindled, it burns violently, emits white light, releases heat, and generates a gas that makes the clarified lime water turbid, that is, the bottle is oxygen.

The resulting gas is passed into the clarified lime water, which becomes turbid, proving that the gas is carbon dioxide.

Oxygen is chemically more reactive. With the exception of rare gases and less reactive metal elements such as gold, platinum, and silver, most of the elements can react with oxygen, and these reactions are called oxidation reactions, and the compounds produced by the reactions (composed of two elements, one of which is oxygen) are called oxides.

The first is to pass two gases into the clear lime water respectively, so that the lime water becomes turbid carbon dioxide gas, and the other is oxygen;

The second type: use a small wooden stick with sparks to put it into the mouth of a gas collection bottle filled with gas, the small wooden stick burns oxygen, and the other bottle is carbon dioxide gas;

The third type is to add a positive burning magnesium strip to the gas collection cylinder, and the black solid is carbon dioxide, and the white solid is oxygen.

Oxygen: Under normal conditions, oxygen is a colorless, odorless gas, not easily soluble in water, under standard conditions, the density of oxygen is slightly greater than that of air, at a pressure of 101kpa, oxygen becomes a light blue liquid at about -183, and at about -218 it becomes a snowflake-like light blue solid.

Carbon dioxide: It is a colorless and odorless gas that can be dissolved in water at room temperature, and its density is greater than that of air. The solid becomes dry ice, which absorbs heat during sublimation, and carbon dioxide is a good chemical raw material and greenhouse fertilizer, but it does not support combustion.