(2) the reaction rate can be controlled; 2H 2o 2 2H 2o+O2↑； Concentrated sulfuric acid; ?
(3) no; ? (4)C； ? (5) A; ? (6) answer.
Examination analysis: (1) memorize the names and uses of commonly used instruments: ① long-necked funnel; 2 is a test tube;
(2) Comparing devices B and A, we can know that the main difference between them is that B chooses a separatory funnel, and the reaction rate can be controlled by rotating the piston of the separatory funnel;
Device B is suitable for producing oxygen from hydrogen peroxide solution and manganese dioxide. Manganese dioxide is used as catalyst, and the reaction equation is: 2h2o 22h2o+O2 ↑;
Device d is suitable for liquid as desiccant, so concentrated sulfuric acid can be used to dry oxygen;
(3) Because the excess hydrogen will overflow the test tube, the device cannot be used as a device for reducing copper oxide by hydrogen, so the rubber stopper should be removed and the catheter should be extended above the copper oxide at the bottom of the test tube;
(4) The solid mixture of ammonium chloride and hydrated lime is usually heated in the laboratory to produce ammonia, so the generator is characterized by solid heating type C device;
(5) Because the density of ammonia gas is less than that of air, it will gather above the gas container, so the gas inlet is a short pipe;
(6) The residue of heating the mixture of potassium chlorate and manganese dioxide is soluble potassium chloride and insoluble manganese dioxide, so it can be purified by filtration; Therefore, to recover MnO 2 from the residue after the reaction, manganese dioxide can be obtained by dissolution and then filtration, and then dried manganese dioxide can be obtained by washing and drying, so the operation steps are dissolution, filtration, washing and drying, so a.
Comments: This topic is not difficult to examine the knowledge of the generation device and collection method of common gases, the writing of reaction principle, the separation of mixtures and so on, and to evaluate the device. The key is to master the selection and flexible application of generating device and collection method; When analyzing the separation method of mixture, we should grasp the nature of matter and analyze it with the principle of separation method.