Hydrogen peroxide to oxygen experiment? Hydrogen peroxide is used in laboratories to produce oxygen

Hydrogen peroxide to produce oxygen can be used as a method of long-neck funnel liquid seal, but he can not control the speed of the reaction, and it is not easy to control the progress of the reaction, and with the separating funnel, the speed of the reaction can be controlled, and it is also easy to control whether the reaction is carried out, so the operation is more convenient and the control is also convenient.

Liquid seals are usually used for volatile liquids, and the boiling point of hydrogen peroxide is about 150, so there is no need for liquid seals.

Hydrogen peroxide solutions that have been left in the laboratory for a long time deteriorate because they break down into water and oxygen. At room temperature, hydrogen peroxide separates and releases oxygen, but at a very, very slow rate, which is invisible to the naked eye. In order to speed up the reaction, we can use heating, that is, hydrogen peroxide will decompose oxygen relatively quickly when heated ("relatively fast" is compared to room temperature), but at the same time, a large amount of water vapor will also evaporate, so this method is not an ideal method for preparing oxygen in the laboratory.

But heating does produce oxygen. The most ideal method for producing oxygen in the laboratory: manganese dioxide is added to the hydrogen peroxide solution at room temperature, which acts as a catalytic effect and can accelerate the reaction.

1 method of producing oxygen:

2. The reactant is: hydrogen peroxide.

3. Reaction conditions: manganese dioxide and other catalysts, the effect is to accelerate the decomposition rate of hydrogen peroxide.

4 Products: oxygen and water.

The 5 equation is: 2 molecules of hydrogen peroxide are decomposed into 2 molecules of hydrogen and 1 molecule of oxygen under the action of manganese dioxide and other catalysts.

6. Experimental drugs: 3% hydrogen peroxide solution, small wooden strips, manganese dioxide solid.

7 Experimental Procedures:

81. Add a small amount of hydrogen peroxide solution to the test tube, put a small wooden strip with sparks at the mouth of the test tube, and observe that there is no obvious phenomenon.

92. Add a small amount of manganese dioxide to the test tube, and observe the phenomenon as follows: a large number of bubbles appear, and the wooden strips rekindle.

103. When the formation of bubbles is stopped, continue to add hydrogen peroxide solution, and the observed phenomenon is: a large number of bubbles appear, and the wooden strips rekindle. It can be concluded that hydrogen peroxide produces oxygen in the presence of a catalyst.

The separating funnel with a piston prevents the generated oxygen from escaping.

The laboratory uses hydrogen peroxide to produce oxygen by draining the water method, and catalysts are needed for the catalytic decomposition of hydrogen peroxide, and the commonly used catalysts mainly include manganese dioxide, ferric oxide, copper chloride, etc.

Experimental drugs and instruments] Erlenmeyer flasks, long-neck funnels, double-hole rubber stoppers, catheters, collection or gas cylinders, water tanks, etc. Answer: Erlenmeyer flasks, long-neck funnels, double-hole rubber stoppers, catheters, gas collection bottles, sinks, hydrogen peroxide solutions, etc.;

Experimental principle] 2H2O2 = MNO = 2H2O+ O2 Reaction conditions] Manganese dioxide - catalyst (accelerate the decomposition rate of hydrogen peroxide) Experimental procedure] Connecting device.

Check the airtightness of the device. The method is to add water to the long-necked funnel until the lower end of the long-necked funnel is submerged, and then immerse one end of the catheter in water, and hold the outer wall of the Erlenmeyer flask with your hand.

Then fill the Erlenmeyer flask with manganese dioxide.

Pour in hydrogen peroxide solution.

Collect oxygen. Full Completion and Inspection.

1. Assemble the experimental device according to the device diagram.

2. Check the air tightness first, and the test tube is evenly heated: "test tube tilting" means that when installing a large test tube, the test tube should be slightly tilted, that is, the test tube mouth should be lower than the bottom of the test tube, so as to prevent the small amount of water contained in the medicine socks trapped in the chain from turning into water vapor when heating, and condensing into water droplets at the nozzle and backflowing, resulting in the rupture of the test tube. "Evenly heated" means that the test tube must be heated evenly when heated.

3. Make the hydrogen peroxide solution in the separating funnel come into contact with the manganese dioxide in the Erlenmeyer flask, use the separating funnel to control the reaction speed, and use the manganese dioxide as a catalyst to observe the experimental phenomenon, and bubbles appear in the water of the gas collection cylinder.

4. Common drainage method for gas collection: It means that oxygen should be collected by drainage gas collection method.

5. Remove the catheter first and then move the lamp: It means that when stopping the oxygen production, be sure to withdraw the trachea from the sink first, and then remove the alcohol lamp.